U.S. patent number 10,047,118 [Application Number 15/523,453] was granted by the patent office on 2018-08-14 for c17-aryl substituted betulinic acid analogs.
This patent grant is currently assigned to ViiV HEALTHCARE UK (NO.5) LIMITED. The grantee listed for this patent is ViiV Healthcare UK (No.5) Limited. Invention is credited to Jie Chen, Yan Chen, Nicholas A. Meanwell, Alicia Regueiro-Ren, Ny Sin, Sing-Yuen Sit.
United States Patent |
10,047,118 |
Chen , et al. |
August 14, 2018 |
C17-aryl substituted betulinic acid analogs
Abstract
Compounds having drug and bio-affecting properties, their
pharmaceutical compositions and methods of use are set forth. In
particular, betulinic acid derivatives that possess unique
antiviral activity are provided as HIV maturation inhibitors, as
represented by compounds of Formula I: ##STR00001## These compounds
are useful for the treatment of HIV and AIDS.
Inventors: |
Chen; Jie (Wallingford, CT),
Chen; Yan (Wallingford, CT), Meanwell; Nicholas A.
(Wallingford, CT), Regueiro-Ren; Alicia (Wallingford,
CT), Sin; Ny (Wallingford, CT), Sit; Sing-Yuen
(Wallingford, CT) |
Applicant: |
Name |
City |
State |
Country |
Type |
ViiV Healthcare UK (No.5) Limited |
Brentford, Middlesex |
N/A |
GB |
|
|
Assignee: |
ViiV HEALTHCARE UK (NO.5)
LIMITED (Brentford, Middlesex, GB)
|
Family
ID: |
54697683 |
Appl.
No.: |
15/523,453 |
Filed: |
November 12, 2015 |
PCT
Filed: |
November 12, 2015 |
PCT No.: |
PCT/US2015/060353 |
371(c)(1),(2),(4) Date: |
May 01, 2017 |
PCT
Pub. No.: |
WO2016/077569 |
PCT
Pub. Date: |
May 19, 2016 |
Prior Publication Data
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Document
Identifier |
Publication Date |
|
US 20170305962 A1 |
Oct 26, 2017 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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62079966 |
Nov 14, 2014 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07J
63/008 (20130101); A61P 31/18 (20180101) |
Current International
Class: |
C07J
63/00 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2009073818 |
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Jun 2009 |
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WO |
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2012106190 |
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Aug 2012 |
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WO |
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2013117137 |
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Aug 2013 |
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WO |
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2013160810 |
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Oct 2013 |
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WO |
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Other References
HIV Vaccines [online]. Retrieved from the internet on Jul. 6, 2017
URL:
<http://www.hiv.gov/hiv-basics/hiv-prevention/potential-future-options-
/hiv-vaccines>. cited by examiner .
HIV Vaccine: How Close Are We? [online]. Retrieved from the
internet on Jul. 6, 2017 URL:
<http://www.healthline.com/health/hiv-aids/vaccine-how-close-are-we>-
;. cited by examiner.
|
Primary Examiner: Jackson; Shawquia
Attorney, Agent or Firm: Brink; Robert H. Gimmi; Edward R.
Majarian; William R.
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATION
This application is a .sctn. 371 of International Application No.
PCT/US2015/060353, filed 12 Nov. 2015, which claims the benefit of
U.S. Provisional Application No. 62/079,966, filed 14 Nov. 2014,
which are incorporated herein in their entireties.
Claims
What is claimed is:
1. A compound of Formula I: ##STR00033## or a pharmaceutically
acceptable salt thereof; wherein R.sub.1 is isopropenyl or
isopropyl; X is selected from the group of phenyl, heteroaryl,
C.sub.4-8 cycloalkyl, C.sub.4-8 cycloalkenyl, C.sub.4-9
spirocycloalkyl, C.sub.4-9 spirocycloalkenyl,
C.sub.4-8oxacycloalkyl, C.sub.6-8 dioxacycloalkenyl, C.sub.6-9
oxaspirocycloalkyl and C.sub.6-9 oxaspirocycloalkenyl ring; wherein
X is substituted with A, wherein A is at least one member selected
from the group of --H, -halo, -hydroxyl, --C.sub.1-6 alkyl,
--C.sub.1-6 alkoxy, --C.sub.1-6haloalkyl, --CN, --COOR.sub.2,
--CONR.sub.2R.sub.2, --NR.sub.8R.sub.9, and --C.sub.1-6 alkyl-Q, Q
is selected from the group of aryl, heteroaryl, substituted
heteroaryl, --OR.sub.2, --COORS, --NR.sub.2R.sub.2,
--SO.sub.2R.sub.7, --CONHSO.sub.2R.sub.3, and
--CONHSO.sub.2NR.sub.2R.sub.2; R.sub.2 is --H, --C.sub.1-6 alkyl,
-alkylsubstituted C.sub.1-6 alkyl or benzyl; Y is selected from the
group of --COOR.sub.2, --C(O)NR.sub.2SO.sub.2R.sub.3, --C(O
)NHSO.sub.2NR.sub.2R.sub.2, --NR.sub.2SO.sub.2R.sub.2,
--SO.sub.2NR.sub.2R.sub.2, --C.sub.3-6
cycloalkyl-COOR.sub.2,--C.sub.2-6 alkenyl-COOR.sub.2, --C.sub.2-6
alkynyl-COOR.sub.2, --C.sub.1-6 alkyl-COOR.sub.2,
-alkylsubstituted-C.sub.1-6 alkyl --COOR.sub.2,
--CF.sub.2--COOR.sub.2, --NHC(O)(CH.sub.2)n--COOR.sub.2,
--SO.sub.2NR.sub.2C(O)R.sub.2, -tetrazole, and --CONHOH, wherein
n=1-6; W is absent or is .C.ident.C.; Z is a heteroaryl group,
wherein Z can be substituted with --H, --C.sub.1-6 alkyl,
--C.sub.1-6 substituted alkyl, --C.sub.1-6 alkyl-Q.sub.1,
--CONR.sub.10R.sub.11, and --COOR.sub.2; Q.sub.1 is selected from
the group of heteroaryl, substituted heteroaryl, halogen,
--CF.sub.3, --OR.sub.2, --COOR.sub.2, --NR.sub.4R.sub.5,
--CONR.sub.10R.sub.11 and --SO.sub.2R.sub.7; R.sub.3 is --H,
--C.sub.1-6 alkyl, -alkylsubstituted C.sub.1-6 alkyl or benzyl;
R.sub.4 is selected from the group of --H, --C.sub.1-6 alkyl,
--C.sub.1-6 alkyl-C(OR.sub.3).sub.2--C.sub.3-6 cycloalkyl,
--C.sub.1-6 substituted alkyl, --C.sub.1-6 alkyl-C.sub.3-6
cycloalkyl, --C.sub.1-6 alkyl-Q.sub.1, --C.sub.1-6 alkyl-C.sub.3-6
cycloalkyl-Q.sub.1, aryl, heteroaryl, substituted heteroaryl,
--COR.sub.6, --COCOR.sub.6, --SO.sub.2R.sub.7, and
--SO.sub.2NR.sub.2R.sub.2; R.sub.5 is selected from the group of
--H, --C.sub.1-6 alkyl, --C.sub.3-6 cycloalkyl, --C.sub.1-6
alkylsubstituted alkyl, --C.sub.1-6 alkyl-NR.sub.8R.sub.9,
--COR.sub.10, --COR.sub.6, --COCOR.sub.6, --SO.sub.2R.sub.7 and
--SO.sub.2NR.sub.2R.sub.2; or R.sub.4 and R.sub.5 are taken
together with the adjacent N to form a cycle selected from the
group of: ##STR00034## with the proviso that only one of R.sub.4 or
R.sub.5 can be selected from the group of --COR.sub.6,
--COCOR.sub.6, --SO.sub.2R.sub.7 and --SO.sub.2NR.sub.2R.sub.2;
R.sub.6 is selected from the group of --H, --C.sub.1-6 alkyl,
--C.sub.1-6 alkyl-substitutedalkyl, --C.sub.3-6 cycloalkyl,
--C.sub.3-6 substitutedcycloalkyl-Q.sub.2, --C.sub.1-6
alkyl-Q.sub.2, --C.sub.1-6
alkyl-substitutedalkyl-Q.sub.2,--C.sub.3-6 cycloalkyl-Q.sub.2,
aryl-Q.sub.2, --NR.sub.2R.sub.2, and --OR.sub.3; Q.sub.2 is
selected from the group of aryl, heteroaryl, substituted
heteroaryl, --OR.sub.2, --COOR.sub.2, --NR.sub.8R.sub.9,
SO.sub.2R.sub.7, --CONHSO.sub.2R.sub.3, and
--CONHSO.sub.2NR.sub.2R.sub.2; R.sub.7 is selected from the group
of --H, --C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl,
--C.sub.3-6 cycloalkyl, --CF.sub.3, aryl, and heteroaryl; R.sub.8
and R.sub.9 are independently selected from the group of --H,
--C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl, aryl, heteroaryl,
substituted aryl, substituted heteroaryl, --C.sub.1-6
alkyl-Q.sub.2, and --COOR.sub.3, or R.sub.8 and R.sub.9 are taken
together with the adjacent N to form a cycle selected from the
group of: ##STR00035## with the proviso that only one of R.sub.8 or
R.sub.9 can be --COOR.sub.3; R.sub.10 is selected from the group of
--H, --C.sub.1-6 alkyl, --NR.sub.2R.sub.2, and --COOR.sub.3;
R.sub.11 is selected from the group of --H, --C.sub.1-6 alkyl,
--C.sub.1-6 alkyl-OH; --C.sub.1-6 alkyl, --C.sub.1-6 substituted
alkyl,--C.sub.3-6 cycloalkyl, --COR.sub.7, --COONR.sub.2R.sub.2,
--SOR.sub.7, and --SONR.sub.2R.sub.2; and R.sub.12 is selected from
the group of --H, --C.sub.1-6 alkyl, --COOR.sub.3, and aryl.
2. A compound or salt as claimed in claim 1, wherein X is
phenyl.
3. A compound or salt as claimed in claim 2, wherein Y is
--COOH.
4. A compound selected from the group consisting of: ##STR00036##
##STR00037## and pharmaceutically acceptable salts thereof.
5. A compound selected from the group consisting of: ##STR00038##
##STR00039## and pharmaceutically acceptable salts thereof.
6. A composition which comprises a compound or salt as claimed in
claim 1, together with one or more pharmaceutically acceptable
carriers, excipients, and/or diluents.
7. A composition which comprises a compound or salt as claimed in
claim 4, together with one or more pharmaceutically acceptable
carriers, excipients, and/or diluents.
Description
FIELD OF THE INVENTION
The present invention relates to novel compounds useful against HIV
and, more particularly, to compounds derived from betulinic acid
and other structurally-related compounds which are useful as HIV
maturation inhibitors, and to pharmaceutical compositions
containing same, as well as to methods for their preparation.
BACKGROUND OF THE INVENTION
HIV-1 (human immunodeficiency virus-1) infection remains a major
medical problem, with an estimated 45-50 million people infected
worldwide at the end of 2010. The number of cases of HIV and AIDS
(acquired immunodeficiency syndrome) has risen rapidly. In 2005,
approximately 5.0 million new infections were reported, and 3.1
million people died from AIDS. Currently available drugs for the
treatment of HIV include nucleoside reverse transcriptase (RT)
inhibitors or approved single pill combinations: zidovudine (or AZT
or RETROVIR.RTM.), didanosine (or VIDEX.RTM.), stavudine (or
ZERIT.RTM.), lamivudine (or 3TC or EPIVIR.RTM.), zalcitabine (or
DDC or HIVID.RTM.), abacavir succinate (or ZIAGEN.RTM.), Tenofovir
disoproxil fumarate salt (or VIREAD.RTM.), emtricitabine (or
FTC-EMTRIVA.RTM., COMBIVIR.RTM. (contains -3TC plus AZT),
TRIZIVIR.RTM. (contains abacavir, lamivudine, and zidovudine),
EPZICOM.RTM. (contains abacavir and lamivudine), TRUVADA.RTM.
(contains VIREAD.RTM. and)EMTRIVA.RTM.; non-nucleoside reverse
transcriptase inhibitors: nevirapine (or VIRAMUNE.RTM.),
delavirdine (or RESCRIPTOR.RTM.) and efavirenz (or SUSTIVA.RTM.),
ATRIPLA.RTM. (TRUVADA.RTM.+SUSTIVA.RTM.), and etravirine, and
peptidomimetic protease inhibitors or approved formulations:
saquinavir, indinavir, ritonavir, nelfinavir, amprenavir,
lopinavir, KALETRA.RTM. (lopinavir and Ritonavir), darunavir,
atazanavir (REYATAZ.RTM.) and tipranavir (APTIVUS.RTM.) and
cobicistat, and integrase inhibitors such as raltegravir
(ISENTRESS.RTM.), and entry inhibitors such as enfuvirtide (T-20)
(FUZEON.RTM.) and maraviroc (SELZENTRY.RTM.).
Each of these drugs can only transiently restrain viral replication
if used alone. However, when used in combination, these drugs have
a profound effect on viremia and disease progression. In fact,
significant reductions in death rates among AIDS patients have been
recently documented as a consequence of the widespread application
of combination therapy. However, despite these impressive results,
30 to 50% of patients may ultimately fail combination drug
therapies. Insufficient drug potency, non-compliance, restricted
tissue penetration and drug-specific limitations within certain
cell types (e.g. most nucleoside analogs cannot be phosphorylated
in resting cells) may account for the incomplete suppression of
sensitive viruses. Furthermore, the high replication rate and rapid
turnover of HIV-1 combined with the frequent incorporation of
mutations, leads to the appearance of drug-resistant variants and
treatment failures when sub-optimal drug concentrations are
present. Therefore, novel anti-HIV agents exhibiting distinct
resistance patterns, and favorable pharmacokinetic as well as
safety profiles are needed to provide more treatment options.
Improved HIV fusion inhibitors and HIV entry coreceptor antagonists
are two examples of new classes of anti-HIV agents further being
studied by a number of investigators.
HIV attachment inhibitors are a further subclass of antiviral
compounds that bind to the HIV surface glycoprotein gp120, and
interfere with the interaction between the surface protein gp120
and the host cell receptor CD4. Thus, they prevent HIV from
attaching to the human CD4 T-cell, and block HIV replication in the
first stage of the HIV life cycle. The properties of HIV attachment
inhibitors have been improved in an effort to obtain compounds with
maximized utility and efficacy as antiviral agents. In particular,
U.S. Pat. No. 7,354,924 and U.S. Pat. No. 7,745,625 are
illustrative of HIV attachment inhibitors.
Another emerging class of compounds for the treatment of HIV are
called HIV maturation inhibitors. Maturation is the last of as many
as 10 or more steps in HIV replication or the HIV life cycle, in
which HIV becomes infectious as a consequence of several HIV
protease-mediated cleavage events in the gag protein that
ultimately results in release of the capsid (CA) protein.
Maturation inhibitors prevent the HIV capsid from properly
assembling and maturing, from forming a protective outer coat, or
from emerging from human cells. Instead, non-infectious viruses are
produced, preventing subsequent cycles of HIV infection.
Certain derivatives of betulinic acid have now been shown to
exhibit potent anti-HIV activity as HIV maturation inhibitors. For
example, U.S. Pat. No. 7,365,221 discloses monoacylated betulin and
dihydrobetuline derivatives, and their use as anti-HIV agents. As
discussed in the '221 reference, esterification of betulinic acid
(1) with certain substituted acyl groups, such as
3',3'-dimethylglutaryl and 3',3'-dimethylsuccinyl groups produced
derivatives having enhanced activity (Kashiwada, Y., et al., J.
Med. Chem. 39:1016-1017 (1996)). Acylated betulinic acid and
dihydrobetulinic acid derivatives that are potent anti-HIV agents
are also described in U.S. Pat. No. 5,679,828. Esterification of
the hydroxyl in the 3 carbon of betulin with succinic acid also
produced a compound capable of inhibiting HIV-1 activity
(Pokrovskii, A. G., et al., "Synthesis of derivatives of plant
triterpenes and study of their antiviral and immunostimulating
activity," Khimiya y Interesakh Ustoichivogo Razvitiya, Vol. 9, No.
3, pp. 485-491 (2001) (English abstract).
Other references to the use of treating HIV infection with
compounds derived from betulinic acid include US 2005/0239748 and
US 2008/0207573, as well as WO2006/053255, WO2009/100532 and
WO2011/007230.
One HIV maturation compound that has been in development has been
identified as Bevirimat or PA-457, with the chemical formula of
C.sub.36H.sub.56O.sub.6 and the IUPAC name of
3.beta.-(3-carboxy-3-methyl-butanoyloxy) lup-20(29)-en-28-oic
acid.
Reference is also made herein to the applications by Bristol-Myers
Squibb entitled "MODIFIED C-3 BETULINIC ACID DERIVATIVES AS HIV
MATURATION INHIBITORS" U.S. Ser. No. 13/151,706 filed on Jun. 2,
2011 (now U.S. Pat. No. 8,754,068) and "C-28 AMIDES OF MODIFIED C-3
BETULINIC ACID DERIVATIVES AS HIV MATURATION INHIBITORS" U.S. Ser.
No. 13/151,722, filed on Jun. 2, 2011 (now U.S. Pat. No.
8,802,661). Reference is also made to the application entitled
"C-28 AMINES OF C-3 MODIFIED BETULINIC ACID DERIVATIVES AS HIV
MATURATION INHIBITORS" U.S. Ser. No. 13/359,680, filed on Jan. 27,
2012 (now U.S. Pat. No. 8,748,415). In addition, reference is made
to the application entitled "C-17 AND C-3 MODIFIED TRITERPENOIDS
WITH HIV MATURATION INHIBITORY ACTIVITY" U.S. Ser. No. 13/359,727
filed on Jan. 27, 2012 (now U.S. Pat. No. 8,846,647). Further
reference is also made to the application "C-3 CYCLOALKENYL
TRITERPENOIDS WITH HIV MATURATION INHIBITORY ACTIVITY" filed U.S.
Ser. No. 13/760,726 on Feb. 6, 2013 (now U.S. Pat. No. 8,906,889),
as well as to the application entitled "TRITERPENOIDS WITH HIV
MATURATION INHIBITORY ACTIVITY" U.S. Ser. No. 14/682,179 filed on
Apr. 9, 2015.
What is now needed in the art are new compounds which are useful as
HIV maturation inhibitors, as well as new pharmaceutical
compositions containing these compounds.
SUMMARY OF THE INVENTION
The present invention provides compounds of Formula I below,
including pharmaceutically acceptable salts thereof, their
pharmaceutical formulations, and their use in patients suffering
from or susceptible to a virus such as HIV. The compounds of
Formula I are effective antiviral agents, particularly as
inhibitors of HIV. They are useful for the treatment of HIV and
AIDS.
One embodiment of the present invention is directed to a compound,
including pharmaceutically acceptable salts thereof, which is
selected from a compound of Formula I:
##STR00002## wherein R.sub.1 is isopropenyl or isopropyl; X is
selected from the group of phenyl, heteroaryl, C.sub.4-8
cycloalkyl, C.sub.4-8 cycloalkenyl, C.sub.4-9 spirocycloalkyl,
C.sub.4-9 spirocycloalkenyl, C.sub.4-8 oxacycloalkyl, C.sub.6-8
dioxacycloalkenyl, C.sub.6-9 oxaspirocycloalkyl and C.sub.6-9
oxaspirocycloalkenyl ring; wherein X is substituted with A, wherein
A is at least one member selected from the group of --H, -halo,
-hydroxyl, --C.sub.1-6 alkyl, --C.sub.1-6 alkoxy,
--C.sub.1-6haloalkyl, --CN, --COOR.sub.2, --CONR.sub.2R.sub.2,
--NR.sub.8R.sub.9, and --C.sub.1-6 alkyl-Q; Q is selected from the
group of aryl, heteroaryl, substituted heteroaryl, --OR.sub.2,
--COOR.sub.3, --NR.sub.2R.sub.2, --SO.sub.2R.sub.7,
--CONHSO.sub.2R.sub.3, and --CONHSO.sub.2NR.sub.2R.sub.2; R.sub.2
is --H, --C.sub.1-6 alkyl, -alkylsubstituted C.sub.1-6 alkyl or
benzyl; Y is selected from the group of --COOR.sub.2,
--C(O)NR.sub.2SO.sub.2R.sub.3, --C(O)NHSO.sub.2NR.sub.2R.sub.2,
--NR.sub.2SO.sub.2R.sub.2, --SO.sub.2NR.sub.2R.sub.2, --C.sub.3-6
cycloalkyl-COOR.sub.2, --C.sub.2-6 alkenyl-COOR.sub.2, --C.sub.2-6
alkynyl-COOR.sub.2, --C.sub.1-6 alkyl-COOR.sub.2,
-alkylsubstituted-C.sub.1-6 alkyl-COOR.sub.2,
--CF.sub.2--COOR.sub.2, --NHC(O)(CH.sub.2).sub.n--COOR.sub.2,
--SO.sub.2NR.sub.2C(O)R.sub.2, -tetrazole, and --CONHOH, wherein
n=1-6; W is absent or is
##STR00003## Z is a heteroaryl group, wherein Z can be substituted
with --H, --C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl,
--C.sub.1-6 alkyl-Q.sub.1, --CONR.sub.10R.sub.11, and --COOR.sub.2;
Q.sub.1 is selected from the group of heteroaryl, substituted
heteroaryl, halogen, --CF.sub.3, --OR.sub.2, --COOR.sub.2,
--NR.sub.4R.sub.5, --CONR.sub.10R.sub.11 and --SO.sub.2R.sub.7;
R.sub.3 is --H, --C.sub.1-6 alkyl, -alkylsubstituted C.sub.1-6
alkyl or benzyl; R.sub.4 is selected from the group of --H,
--C.sub.1-6 alkyl, --C.sub.1-6 alkyl-C(OR.sub.3).sub.2--C.sub.3-6
cycloalkyl, --C.sub.1-6 substituted alkyl, --C.sub.1-6
alkyl-C.sub.3-6 cycloalkyl, --C.sub.1-6 alkyl-Q.sub.1, --C.sub.1-6
alkyl-C.sub.3-6 cycloalkyl-Q.sub.1, aryl, heteroaryl, substituted
heteroaryl, --COR.sub.6, --COCOR.sub.6, --SO.sub.2R.sub.7, and
--SO.sub.2NR.sub.2R.sub.2; R.sub.5 is selected from the group of
--H, --C.sub.1-6 alkyl, --C.sub.3-6 cycloalkyl, --C.sub.1-6
alkylsubstituted alkyl, --C.sub.1-6 alkyl-NR.sub.8R.sub.9,
--COR.sub.10, --COR.sub.6, --COCOR.sub.6, --SO.sub.2R.sub.7 and
--SO.sub.2NR.sub.2R.sub.2; or R.sub.4 and R.sub.5 are taken
together with the adjacent N to form a cycle selected from the
group of:
##STR00004## with the proviso that only one of R.sub.4 or R.sub.5
can be selected from the group of --COR.sub.6, --COCOR.sub.6,
--SO.sub.2R.sub.7 and --SO.sub.2NR.sub.2R.sub.2; R.sub.6 is
selected from the group of --H, --C.sub.1-6 alkyl, --C.sub.1-6
alkyl-substitutedalkyl, --C.sub.3-6 cycloalkyl, --C.sub.3-6
substitutedcycloalkyl-Q.sub.2, --C.sub.1-6 alkyl-Q.sub.2,
--C.sub.1-6 alkyl-substitutedalkyl-Q.sub.2, --C.sub.3-6
cycloalkyl-Q.sub.2, aryl-Q.sub.2, --NR.sub.2R.sub.2, and
--OR.sub.3; Q.sub.2 is selected from the group of aryl, heteroaryl,
substituted heteroaryl, --OR.sub.2, --COOR.sub.2,
--NR.sub.8R.sub.9, SO.sub.2R.sub.7, --CONHSO.sub.2R.sub.3, and
--CONHSO.sub.2NR.sub.2R.sub.2; R.sub.7 is selected from the group
of --H, --C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl,
--C.sub.3-6 cycloalkyl, --CF.sub.3, aryl, and heteroaryl; R.sub.8
and R.sub.9 are independently selected from the group of --H,
--C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl, aryl, heteroaryl,
substituted aryl, substituted heteroaryl, --C.sub.1-6
alkyl-Q.sub.2, and --COOR.sub.3, or R.sub.8 and R.sub.9 are taken
together with the adjacent N to form a cycle selected from the
group of:
##STR00005## with the proviso that only one of R.sub.8 or R.sub.9
can be --COOR.sub.3; R.sub.10 is selected from the group of --H,
--C.sub.1-6 alkyl, --NR.sub.2R.sub.2, and --COOR.sub.3; R.sub.11 is
selected from the group of --H, --C.sub.1-6 alkyl, --C.sub.1-6
alkyl-OH; --C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl,
--C.sub.3-6 cycloalkyl, --COR.sub.7, --COONR.sub.2R.sub.2,
--SOR.sub.7, and --SONR.sub.2R.sub.2; and R.sub.12 is selected from
the group of --H, --C.sub.1-6 alkyl, --COOR.sub.3, and aryl.
In a further embodiment, there is provided a method for treating
mammals infected with a virus, especially wherein said virus is
HIV, comprising administering to said mammal an antiviral effective
amount of a compound which is selected from the group of compounds
of Formula I, and one or more pharmaceutically acceptable carriers,
excipients or diluents. Optionally, the compound of Formula I can
be administered in combination with an antiviral effective amount
of another AIDS treatment agent selected from the group consisting
of: (a) an AIDS antiviral agent; (b) an anti-infective agent; (c)
an immunomodulator; and (d) other HIV entry inhibitors.
Another embodiment of the present invention is a pharmaceutical
composition comprising one or more compounds of Formula I, and one
or more pharmaceutically acceptable carriers, excipients, and/or
diluents; and optionally in combination with another AIDS treatment
agent selected from the group consisting of: (a) an AIDS antiviral
agent; (b) an anti-infective agent; (c) an immunomodulator; and (d)
other HIV entry inhibitors.
In another embodiment of the invention there is provided one or
more methods for making the compounds of Formula I herein.
Also provided herein are intermediate compounds useful in making
the compounds of Formula I herein.
The present invention is directed to these, as well as other
important ends, hereinafter described.
DETAILED DESCRIPTION OF THE EMBODIMENTS
As used herein, the singular forms "a", "an", and "the" include
plural reference unless the context clearly dictates otherwise.
Since the compounds of the present invention may possess asymmetric
centers and therefore occur as mixtures of diastereomers, the
present disclosure includes the individual diastereoisomeric forms
of the compounds of Formula I in addition to the mixtures
thereof.
Definitions
Unless otherwise specifically set forth elsewhere in the
application, one or more of the following terms may be used herein,
and shall have the following meanings:
"H" refers to hydrogen, including its isotopes, such as
deuterium.
The term "C.sub.1-6 alkyl" as used herein and in the claims (unless
specified otherwise) mean straight or branched chain alkyl groups
such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl,
amyl, hexyl and the like.
"C.sub.1-C.sub.4 fluoroalkyl" refers to F-substituted
C.sub.1-C.sub.4 alkyl wherein at least one H atom is substituted
with F atom, and each H atom can be independently substituted by F
atom;
"Halogen" or "halo" refers to chlorine, bromine, iodine or
fluorine.
An "aryl" or "Ar" group refers to an all carbon monocyclic or
fused-ring polycyclic (i.e., rings which share adjacent pairs of
carbon atoms) groups having a completely conjugated pi-electron
system. Examples, without limitation, of aryl groups are phenyl,
naphthalenyl and anthracenyl. The aryl group may be substituted or
unsubstituted. When substituted, the substituent group(s) are
preferably one or more selected from alkyl, cycloalkyl, aryl,
heteroaryl, heteroalicyclic, hydroxy, alkoxy, aryloxy,
heteroaryloxy, heteroalicycloxy, thiohydroxy, thioaryloxy,
thioheteroaryloxy, thioheteroalicycloxy, cyano, halogen, nitro,
carbonyl, O-carbamyl, N-carbamyl, C-amido, N-amido, C-carboxy,
O-carboxy, sulfinyl, sulfonyl, sulfonamido, trihalomethyl, ureido,
amino and --NR.sup.xR.sup.y, wherein R.sup.x and R.sup.y are
independently selected from the group consisting of hydrogen,
alkyl, cycloalkyl, aryl, carbonyl, C-carboxy, sulfonyl,
trihalomethyl, and, combined, a five- or six-member heteroalicyclic
ring.
A "heteroaryl" group refers to a monocyclic or fused ring (i.e.,
rings which share an adjacent pair of atoms) group having in the
ring(s) one or more atoms selected from the group consisting of
nitrogen, oxygen and sulfur and, in addition, having a completely
conjugated pi-electron system. Unless otherwise indicated, the
heteroaryl group may be attached at either a carbon or nitrogen
atom within the heteroaryl group. It should be noted that the term
heteroaryl is intended to encompass an N-oxide of the parent
heteroaryl if such an N-oxide is chemically feasible as is known in
the art. Examples, without limitation, of heteroaryl groups are
furyl, thienyl, benzothienyl, thiazolyl, imidazolyl, oxazolyl,
oxadiazolyl, thiadiazolyl, benzothiazolyl, triazolyl, tetrazolyl,
isoxazolyl, isothiazolyl, pyrrolyl, pyranyl, tetrahydropyranyl,
pyrazolyl, pyridyl, pyrimidinyl, quinolinyl, isoquinolinyl,
purinyl, carbazolyl, benzoxazolyl, benzimidazolyl, indolyl,
isoindolyl, pyrazinyl. diazinyl, pyrazine, triazinyl, tetrazinyl,
and tetrazolyl. When substituted the substituted group(s) is
preferably one or more selected from alkyl, cycloalkyl, aryl,
heteroaryl, heteroalicyclic, hydroxy, alkoxy, aryloxy,
heteroaryloxy, heteroalicycloxy, thioalkoxy, thiohydroxy,
thioaryloxy, thioheteroaryloxy, thioheteroalicycloxy, cyano,
halogen, nitro, carbonyl, O-carbamyl, N-carbamyl, C-amido, N-amido,
C-carboxy, O-carboxy, sulfinyl, sulfonyl, sulfonamido,
trihalomethyl, ureido, amino, and --NR.sup.xR.sup.y, wherein
R.sup.x and R.sup.y are as defined above.
A "heteroalicyclic" group refers to a monocyclic or fused ring
group having in the ring(s) one or more atoms selected from the
group consisting of nitrogen, oxygen and sulfur. Rings are selected
from those which provide stable arrangements of bonds and are not
intended to encompass systems which would not exist. The rings may
also have one or more double bonds. However, the rings do not have
a completely conjugated pi-electron system. Examples, without
limitation, of heteroalicyclic groups are azetidinyl, piperidyl,
piperazinyl, imidazolinyl, thiazolidinyl, 3-pyrrolidin-1-yl,
morpholinyl, thiomorpholinyl and its S oxides and
tetrahydropyranyl. When substituted the substituted group(s) is
preferably one or more selected from alkyl, cycloalkyl, aryl,
heteroaryl, heteroalicyclic, hydroxy, alkoxy, aryloxy,
heteroaryloxy, heteroalicycloxy, thiohydroxy, thioalkoxy,
thioaryloxy, thioheteroaryloxy, thioheteroalicycloxy, cyano,
halogen, nitro, carbonyl, thiocarbonyl, O-carbamyl, N-carbamyl,
O-thiocarbamyl, N-thiocarbamyl, C-amido, C-thioamido, N-amido,
C-carboxy, O-carboxy, sulfinyl, sulfonyl, sulfonamido,
trihalomethanesulfonamido, trihalomethanesulfonyl, silyl, guanyl,
guanidino, ureido, phosphonyl, amino and --NR.sup.xR.sup.y, wherein
R.sup.x and R.sup.y are as defined above.
An "alkyl" group refers to a saturated aliphatic hydrocarbon
including straight chain and branched chain groups. Preferably, the
alkyl group has 1 to 20 carbon atoms (whenever a numerical range;
e.g., "1-20", is stated herein, it means that the group, in this
case the alkyl group may contain 1 carbon atom, 2 carbon atoms, 3
carbon atoms, etc. up to and including 20 carbon atoms). More
preferably, it is a medium size alkyl having 1 to 10 carbon atoms.
Most preferably, it is a lower alkyl having 1 to 4 carbon atoms.
The alkyl group may be substituted or unsubstituted. When
substituted, the substituent group(s) is preferably one or more
individually selected from trihaloalkyl, cycloalkyl, aryl,
heteroaryl, heteroalicyclic, hydroxy, alkoxy, aryloxy,
heteroaryloxy, heteroalicycloxy, thiohydroxy, thioalkoxy,
thioaryloxy, thioheteroaryloxy, thioheteroalicycloxy, cyano, halo,
nitro, carbonyl, thiocarbonyl, O-carbamyl, N-carbamyl,
O-thiocarbamyl, N-thiocarbamyl, C-amido, C-thioamido, N-amido,
C-carboxy, O-carboxy, sulfinyl, sulfonyl, sulfonamido,
trihalomethanesulfonamido, trihalomethanesulfonyl, and combined, a
five- or six-member heteroalicyclic ring.
A "cycloalkyl" group refers to an all-carbon monocyclic or fused
ring (i.e., rings which share and adjacent pair of carbon atoms)
group wherein one or more rings does not have a completely
conjugated pi-electron system. Examples, without limitation, of
cycloalkyl groups are cyclopropane, cyclobutane, cyclopentane,
cyclopentene, cyclohexane, cyclohexene, cycloheptane, cycloheptene
and adamantane. A cycloalkyl group may be substituted or
unsubstituted. When substituted, the substituent group(s) is
preferably one or more individually selected from alkyl, aryl,
heteroaryl, heteroalicyclic, hydroxy, alkoxy, aryloxy,
heteroaryloxy, heteroalicycloxy, thiohydroxy, thioalkoxy,
thioaryloxy, thioheteroaryloxy, thioheteroalicycloxy, cyano, halo,
nitro, carbonyl, thiocarbonyl, O-carbamyl, N-carbamyl,
O-thiocarbamyl, N-thiocarbamyl, C-amido, C-thioamido, N-amido,
C-carboxy, O-carboxy, sulfinyl, sulfonyl, sulfonamido,
trihalomethanesulfonamido, trihalomethanesulfonyl, silyl, amidino,
guanidino, ureido, phosphonyl, amino and --NR.sup.xR.sup.y with
R.sup.x and R.sup.y as defined above.
An "alkenyl" group refers to an alkyl group, as defined herein,
having at least two carbon atoms and at least one carbon-carbon
double bond.
An "alkynyl" group refers to an alkyl group, as defined herein,
having at least two carbon atoms and at least one carbon-carbon
triple bond.
A "hydroxy" group refers to an --OH group.
An "alkoxy" group refers to both an --O-alkyl and an --O-cycloalkyl
group as defined herein.
An "aryloxy" group refers to both an --O-aryl and an --O-heteroaryl
group, as defined herein.
A "heteroaryloxy" group refers to a heteroaryl-O-group with
heteroaryl as defined herein.
A "heteroalicycloxy" group refers to a heteroalicyclic-O-group with
heteroalicyclic as defined herein.
A "thiohydroxy" group refers to an --SH group.
A "thioalkoxy" group refers to both an S-alkyl and an
--S-cycloalkyl group, as defined herein.
A "thioaryloxy" group refers to both an --S-aryl and an
--S-heteroaryl group, as defined herein.
A "thioheteroaryloxy" group refers to a heteroaryl-S-group with
heteroaryl as defined herein.
A "thioheteroalicycloxy" group refers to a heteroalicyclic-S-group
with heteroalicyclic as defined herein.
A "carbonyl" group refers to a --C(.dbd.O)--R'' group, where R'' is
selected from the group consisting of hydrogen, alkyl, alkenyl,
alkynyl, cycloalkyl, aryl, heteroaryl (bonded through a ring
carbon) and heteroalicyclic (bonded through a ring carbon), as each
is defined herein.
An "aldehyde" group refers to a carbonyl group where R'' is
hydrogen.
A "thiocarbonyl" group refers to a --C(.dbd.S)--R'' group, with R''
as defined herein.
A "keto" group refers to a --CC(.dbd.O)C-group wherein the carbon
on either or both sides of the C.dbd.O may be alkyl, cycloalkyl,
aryl or a carbon of a heteroaryl or heteroalicyclic group.
A "trihalomethanecarbonyl" group refers to a
Z.sub.3CC(.dbd.O)-group with said Z being a halogen.
A "C-carboxy" group refers to a --C(.dbd.O)O--R'' groups, with R''
as defined herein.
An "O-carboxy" group refers to a R''C(--O)O-group, with R'' as
defined herein.
A "carboxylic acid" group refers to a C-carboxy group in which R''
is hydrogen.
A "trihalomethyl" group refers to a --CZ.sub.3, group wherein Z is
a halogen group as defined herein.
A "trihalomethanesulfonyl" group refers to an
Z.sub.3CS(.dbd.O)2-groups with Z as defined above.
A "trihalomethanesulfonamido" group refers to a
Z.sub.3CS(.dbd.O).sub.2NR.sup.x-group with Z as defined above and
R.sup.x being H or (C.sub.1-6)alkyl.
A "sulfinyl" group refers to a --S(.dbd.O)--R'' group, with R''
being (C.sub.1-6)alkyl.
A "sulfonyl" group refers to a --S(.dbd.O).sub.2R'' group with R''
being (C.sub.1-6)alkyl.
A "S-sulfonamido" group refers to a
--S(.dbd.O).sub.2NR.sup.XR.sup.Y, with R.sup.X and R.sup.Y
independently being H or (C.sub.1-6)alkyl.
A "N-sulfonamido" group refers to a
R''S(.dbd.O).sub.2NR.sub.x-group, with R.sub.x being H or
(C.sub.1-6)alkyl.
A "O-carbamyl" group refers to a --OC(.dbd.O)NR.sup.xR.sup.y group,
with R.sup.X and R.sup.Y independently being H or
(C.sub.1-6)alkyl.
A "N-carbamyl" group refers to a R.sup.xOC(.dbd.O)NR.sup.y group,
with R.sup.x and R.sup.y independently being H or
(C.sub.1-6)alkyl.
A "O-thiocarbamyl" group refers to a --OC(.dbd.S)NR.sup.xR.sup.y
group, with R.sup.x and R.sup.y independently being H or
(C.sub.1-6)alkyl.
A "N-thiocarbamyl" group refers to a
R.sup.xOC(.dbd.S)NR.sup.y-group, with R.sup.x and R.sup.y
independently being H or (C.sub.1-6)alkyl.
An "amino" group refers to an --NH.sub.2 group.
A "C-amido" group refers to a --C(.dbd.O)NR.sup.xR.sup.y group,
with R.sup.x and R.sup.y independently being H or
(C.sub.1-6)alkyl.
A "C-thioamido" group refers to a --C(.dbd.S)NR.sup.xR.sup.y group,
with R.sup.x and R.sup.y independently being H or
(C.sub.1-6)alkyl.
A "N-amido" group refers to a R.sup.xC(.dbd.O)NR.sup.y-group, with
R.sup.x and R.sup.y independently being H or (C.sub.1-6)alkyl.
An "ureido" group refers to a --NR.sup.xC(.dbd.O)NR.sup.yR.sup.y2
group, with R.sup.x, R.sup.y, and R.sup.y2 independently being H or
(C.sub.1-6)alkyl.
A "guanidino" group refers to a --R.sup.xNC(.dbd.N)NR.sup.yR.sup.y2
group, with R.sup.x, R.sup.y, and R.sup.y2 independently being H or
(C.sub.1-6)alkyl.
A "amidino" group refers to a R.sup.xR.sup.yNC(.dbd.N)-group, with
R.sup.x and R.sup.y independently being H or (C.sub.1-6)alkyl.
A "cyano" group refers to a --CN group.
A "silyl" group refers to a --Si(R'').sub.3, with R'' being
(C.sub.1-6)alkyl or phenyl.
A "phosphonyl" group refers to a P(.dbd.O)(OR.sup.x).sub.2 with
R.sup.x being (C.sub.1-6)alkyl.
A "hydrazino" group refers to a --NR.sup.xNR.sup.yR.sup.y2 group,
with R.sup.x, R.sup.y, and R.sup.y2 independently being H or
(C.sub.1-6)alkyl. A "4, 5, or 6 membered ring cyclic N-lactam"
group refers to
##STR00006##
A "spiro" group is a bicyclic organic group with rings connected
through just one atom. The rings can be different in nature or
identical. The connecting atom is also called the spiroatom, most
often a quaternary carbon ("spiro carbon").
An "oxospiro" or "oxaspiro" group is a spiro group having an oxygen
contained within the bicyclic ring structure. A "dioxospiro" or
"dioxaspiro" group has two oxygens within the bicyclic ring
structure.
Any two adjacent R groups may combine to form an additional aryl,
cycloalkyl, heteroaryl or heterocyclic ring fused to the ring
initially bearing those R groups.
It is known in the art that nitrogen atoms in heteroaryl systems
can be "participating in a heteroaryl ring double bond", and this
refers to the form of double bonds in the two tautomeric structures
which comprise five-member ring heteroaryl groups. This dictates
whether nitrogens can be substituted as well understood by chemists
in the art. The disclosure and claims of the present disclosure are
based on the known general principles of chemical bonding. It is
understood that the claims do not encompass structures known to be
unstable or not able to exist based on the literature.
Pharmaceutically acceptable salts and prodrugs of compounds
disclosed herein are within the scope of the invention. The term
"pharmaceutically acceptable salt" as used herein and in the claims
is intended to include nontoxic base addition salts. Suitable salts
include those derived from organic and inorganic acids such as,
without limitation, hydrochloric acid, hydrobromic acid, phosphoric
acid, sulfuric acid, methanesulfonic acid, acetic acid, tartaric
acid, lactic acid, sulfinic acid, citric acid, maleic acid, fumaric
acid, sorbic acid, aconitic acid, salicylic acid, phthalic acid,
and the like. The term "pharmaceutically acceptable salt" as used
herein is also intended to include salts of acidic groups, such as
a carboxylate, with such counterions as ammonium, alkali metal
salts, particularly sodium or potassium, alkaline earth metal
salts, particularly calcium or magnesium, and salts with suitable
organic bases such as lower alkylamines (methylamine, ethylamine,
cyclohexylamine, and the like) or with substituted lower
alkylamines (e.g. hydroxyl-substituted alkylamines such as
diethanolamine, triethanolamine or
tris(hydroxymethyl)-aminomethane), or with bases such as piperidine
or morpholine.
As stated above, the compounds of the invention also include
"prodrugs". The term "prodrug" as used herein encompasses both the
term "prodrug esters" and the term "prodrug ethers".
As set forth above, the invention is directed to a compound,
including pharmaceutically acceptable salts thereof, which is
selected from a compound of Formula I:
##STR00007## wherein R.sub.1 is isopropenyl or isopropyl; X is
selected from the group of phenyl, heteroaryl, C.sub.4-8
cycloalkyl, C.sub.4-8 cycloalkenyl, C.sub.4-9 spirocycloalkyl,
C.sub.4-9 spirocycloalkenyl, C.sub.4-8 oxacycloalkyl, C.sub.6-8
dioxacycloalkenyl, C.sub.6-9 oxaspirocycloalkyl and C.sub.6-9
oxaspirocycloalkenyl ring; wherein X is substituted with A, wherein
A is at least one member selected from the group of --H, -halo,
-hydroxyl, --C.sub.1-6 alkyl, --C.sub.1-6 alkoxy,
--C.sub.1-6haloalkyl, --CN, --COOR.sub.2, --CONR.sub.2R.sub.2,
--NR.sub.8R.sub.9, and --C.sub.1-6 alkyl-Q; Q is selected from the
group of aryl, heteroaryl, substituted heteroaryl, --OR.sub.2,
--COOR.sub.3, --NR.sub.2R.sub.2, --SO.sub.2R.sub.7,
--CONHSO.sub.2R.sub.3, and --CONHSO.sub.2NR.sub.2R.sub.2; R.sub.2
is --H, --C.sub.1-6 alkyl, -alkylsubstituted C.sub.1-6 alkyl or
benzyl; Y is selected from the group of --COOR.sub.2,
--C(O)NR.sub.2SO.sub.2R.sub.3, --C(O)NHSO.sub.2NR.sub.2R.sub.2,
--NR.sub.2SO.sub.2R.sub.2, --SO.sub.2NR.sub.2R.sub.2, --C.sub.3-6
cycloalkyl-COOR.sub.2, --C.sub.2-6 alkenyl-COOR.sub.2, --C.sub.2-6
alkynyl-COOR.sub.2, --C.sub.1-6 alkyl-COOR.sub.2,
-alkylsubstituted-C.sub.1-6 alkyl-COOR.sub.2,
--CF.sub.2--COOR.sub.2, --NHC(O)(CH.sub.2).sub.n--COOR.sub.2,
--SO.sub.2NR.sub.2C(O)R.sub.2, -tetrazole, and --CONHOH, wherein
n=1-6; W is absent or is
##STR00008## Z is a heteroaryl group, wherein Z can be substituted
with --H, --C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl,
--C.sub.1-6 alkyl-Q.sub.1, --CONR.sub.10R.sub.11, and --COOR.sub.2;
Q.sub.1 is selected from the group of heteroaryl, substituted
heteroaryl, halogen, --CF.sub.3, --OR.sub.2, --COOR.sub.2,
--NR.sub.4R.sub.5, --CONR.sub.10R.sub.11 and --SO.sub.2R.sub.7;
R.sub.3 is --H, --C.sub.1-6 alkyl, -alkylsubstituted C.sub.1-6
alkyl or benzyl; R.sub.4 is selected from the group of --H,
--C.sub.1-6 alkyl, --C.sub.1-6 alkyl-C(OR.sub.3).sub.2--C.sub.3-6
cycloalkyl, --C.sub.1-6 substituted alkyl, --C.sub.1-6
alkyl-C.sub.3-6 cycloalkyl, --C.sub.1-6 alkyl-Q.sub.1, --C.sub.1-6
alkyl-C.sub.3-6 cycloalkyl-Q.sub.1, aryl, heteroaryl, substituted
heteroaryl, --COR.sub.6, --COCOR.sub.6, --SO.sub.2R.sub.7, and
--SO.sub.2NR.sub.2R.sub.2; R.sub.5 is selected from the group of
--H, --C.sub.1-6 alkyl, --C.sub.3-6 cycloalkyl, --C.sub.1-6
alkylsubstituted alkyl, --C.sub.1-6 alkyl-NR.sub.8R.sub.9,
--COR.sub.10, --COR.sub.6, --COCOR.sub.6, --SO.sub.2R.sub.7 and
--SO.sub.2NR.sub.2R.sub.2; or R.sub.4 and R.sub.5 are taken
together with the adjacent N to form a cycle selected from the
group of:
##STR00009## with the proviso that only one of R.sub.4 or R.sub.5
can be selected from the group of --COR.sub.6, --COCOR.sub.6,
--SO.sub.2R.sub.7 and --SO.sub.2NR.sub.2R.sub.2; R.sub.6 is
selected from the group of --H, --C.sub.1-6 alkyl, --C.sub.1-6
alkyl-substitutedalkyl, --C.sub.3-6 cycloalskyl, --C.sub.3-6
substitutedcycloalkyl-Q.sub.2, --C.sub.1-6 alkyl-Q.sub.2,
--C.sub.1-6 alkyl-substitutedalkyl-Q.sub.2, --C.sub.3-6
cycloalkyl-Q.sub.2, aryl-Q.sub.2, --NR.sub.2R.sub.2, and
--OR.sub.3; Q.sub.2 is selected from the group of aryl, heteroaryl,
substituted heteroaryl, --OR.sub.2, --COOR.sub.2,
--NR.sub.8R.sub.9, SO.sub.2R.sub.7, --CONHSO.sub.2R.sub.3, and
--CONHSO.sub.2NR.sub.2R.sub.2; R.sub.7 is selected from the group
of --H, --C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl,
--C.sub.3-6 cycloalkyl, --CF.sub.3, aryl, and heteroaryl; R.sub.8
and R.sub.9 are independently selected from the group of --H,
--C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl, aryl, heteroaryl,
substituted aryl, substituted heteroaryl, --C.sub.1-6
alkyl-Q.sub.2, and --COOR.sub.3, or R.sub.8 and R.sub.9 are taken
together with the adjacent N to form a cycle selected from the
group of:
##STR00010## with the proviso that only one of R.sub.8 or R.sub.9
can be --COOR.sub.3; R.sub.10 is selected from the group of --H,
--C.sub.1-6 alkyl, --NR.sub.2R.sub.2, and --COOR.sub.3; R.sub.11 is
selected from the group of --H, --C.sub.1-6 alkyl, --C.sub.1-6
alkyl-OH; --C.sub.1-6 alkyl, --C.sub.1-6 substituted alkyl,
--C.sub.3-6 cycloalkyl, --COR.sub.7, --COONR.sub.2R.sub.2,
--SOR.sub.7, and --SONR.sub.2R.sub.2; and R.sub.12 is selected from
the group of --H, --C.sub.1-6 alkyl, --COORS, and aryl.
In a preferred embodiment of the invention, X is selected from
phenyl.
It is also preferred that Y is --COOH.
It is further preferred that R.sub.1 is isopropenyl.
Preferred compounds, including pharmaceutically acceptable salts
thereof, as part of the invention include the following:
##STR00011## ##STR00012##
The compounds above represent the mixture of diastereoisomers, and
the two individual disastereomers. In certain embodiments, one of
the specific diastereomers may be particularly preferred.
The compounds of the present invention, according to all the
various embodiments described above, may be administered orally,
parenterally (including subcutaneous injections, intravenous,
intramuscular, intrasternal injection or infusion techniques), by
inhalation spray, or rectally, and by other means, in dosage unit
formulations containing non-toxic pharmaceutically acceptable
carriers, excipients and diluents available to the skilled artisan.
One or more adjuvants may also be included.
Thus, in accordance with the present invention, there is further
provided a method of treatment, and a pharmaceutical composition,
for treating viral infections such as HIV infection and AIDS. The
treatment involves administering to a patient in need of such
treatment a pharmaceutical composition which contains an antiviral
effective amount of one or more of the compounds of Formula I
together with one or more pharmaceutically acceptable carriers,
excipients or diluents. As used herein, the term "antiviral
effective amount" means the total amount of each active component
of the composition and method that is sufficient to show a
meaningful patient benefit, i.e., inhibiting, ameliorating, or
healing of acute conditions characterized by inhibition of HIV
infection. When applied to an individual active ingredient,
administered alone, the term refers to that ingredient alone. When
applied to a combination, the term refers to combined amounts of
the active ingredients that result in the therapeutic effect,
whether administered in combination, serially or simultaneously.
The terms "treat, treating, treatment" as used herein and in the
claims means preventing, inhibiting, ameliorating and/or healing
diseases and conditions associated with HIV infection.
The pharmaceutical compositions of the invention may be in the form
of orally administrable suspensions or tablets; as well as nasal
sprays, sterile injectable preparations, for example, as sterile
injectable aqueous or oleaginous suspensions or suppositories.
Pharmaceutically acceptable carriers, excipients or diluents may be
utilized in the pharmaceutical compositions, and are those utilized
in the art of pharmaceutical preparations.
When administered orally as a suspension, these compositions are
prepared according to techniques typically known in the art of
pharmaceutical formulation and may contain microcrystalline
cellulose for imparting bulk, alginic acid or sodium alginate as a
suspending agent, methylcellulose as a viscosity enhancer, and
sweeteners/flavoring agents known in the art. As immediate release
tablets, these compositions may contain microcrystalline cellulose,
dicalcium phosphate, starch, magnesium stearate and lactose and/or
other excipients, binders, extenders, disintegrants, diluents, and
lubricants known in the art.
The injectable solutions or suspensions may be formulated according
to known art, using suitable non-toxic, parenterally acceptable
diluents or solvents, such as mannitol, 1,3-butanediol, water,
Ringer's solution or isotonic sodium chloride solution, or suitable
dispersing or wetting and suspending agents, such as sterile,
bland, fixed oils, including synthetic mono- or diglycerides, and
fatty acids, including oleic acid.
The compounds herein set forth can be administered orally to humans
in a dosage range of about 1 to 100 mg/kg body weight in divided
doses, usually over an extended period, such as days, weeks,
months, or even years. One preferred dosage range is about 1 to 10
mg/kg body weight orally in divided doses. Another preferred dosage
range is about 1 to 20 mg/kg body weight in divided doses. It will
be understood, however, that the specific dose level and frequency
of dosage for any particular patient may be varied and will depend
upon a variety of factors including the activity of the specific
compound employed, the metabolic stability and length of action of
that compound, the age, body weight, general health, sex, diet,
mode and time of administration, rate of excretion, drug
combination, the severity of the particular condition, and the host
undergoing therapy.
Also contemplated herein are combinations of the compounds of
Formula I herein set forth, together with one or more other agents
useful in the treatment of AIDS. For example, the compounds of this
disclosure may be effectively administered, whether at periods of
pre-exposure and/or post-exposure, in combination with effective
amounts of the AIDS antivirals, immunomodulators, antiinfectives,
or vaccines, such as those in the following non-limiting table:
TABLE-US-00001 Drug Name Manufacturer Indication ANTIVIRALS 097
Hoechst/Bayer HIV infection, AIDS, ARC (non-nucleoside reverse
transcriptase (RT) inhibitor) Amprenavir Glaxo Wellcome HIV
infection, 141 W94 AIDS, ARC GW 141 (protease inhibitor) Abacavir
(1592U89) Glaxo Wellcome HIV infection, GW 1592 AIDS, ARC (RT
inhibitor) Acemannan Carrington Labs ARC (Irving, TX) Acyclovir
Burroughs Wellcome HIV infection, AIDS, ARC AD-439 Tanox Biosystems
HIV infection, AIDS, ARC AD-519 Tanox Biosystems HIV infection,
AIDS, ARC Adefovir dipivoxil Gilead Sciences HIV infection AL-721
Ethigen ARC, PGL (Los Angeles, CA) HIV positive, AIDS Alpha
Interferon Glaxo Wellcome Kaposi's sarcoma, HIV in combination
w/Retrovir Ansamycin Adria Laboratories ARC LM 427 (Dublin, OH)
Erbamont (Stamford, CT) Antibody which Advanced Biotherapy AIDS,
ARC Neutralizes pH Concepts Labile alpha aberrant (Rockville, MD)
Interferon AR177 Aronex Pharm HIV infection, AIDS, ARC
Beta-fluoro-ddA Nat'l Cancer Institute AIDS-associated diseases
BMS-234475 Bristol-Myers Squibb/ HIV infection, (CGP-61755)
Novartis AIDS, ARC (protease inhibitor) CI-1012 Warner-Lambert
HIV-1 infection Cidofovir Gilead Science CMV retinitis, herpes,
papillomavirus Curdlan sulfate AJI Pharma USA HIV infection
Cytomegalovirus MedImmune CMV retinitis Immune globin Cytovene
Syntex Sight threatening Ganciclovir CMV peripheral CMV retinitis
Darunavir Tibotec-J & J HIV infection, AIDS, ARC (protease
inhibitor) Delaviridine Pharmacia-Upjohn HIV infection, AIDS, ARC
(RT inhibitor) Dextran Sulfate Ueno Fine Chem. AIDS, ARC, HIV Ind.
Ltd. (Osaka, positive Japan) asymptomatic ddC Hoffman-La Roche HIV
infection, AIDS, Dideoxycytidine ARC ddI Bristol-Myers Squibb HIV
infection, AIDS, Dideoxyinosine ARC; combination with AZT/d4T
DMP-450 AVID HIV infection, (Camden, NJ) AIDS, ARC (protease
inhibitor) Efavirenz Bristol Myers Squibb HIV infection, (DMP 266,
SUSTIVA .RTM.) AIDS, ARC (-)6-Chloro-4-(S)- (non-nucleoside RT
cyclopropylethynyl- inhibitor) 4(S)-trifluoro- methyl-1,4-dihydro-
2H-3,1-benzoxazin- 2-one, STOCRINE EL10 Elan Corp, PLC HIV
infection (Gainesville, GA) Etravirine Tibotec/J & J HIV
infection, AIDS, ARC (non-nucleoside reverse transcriptase
inhibitor) Famciclovir Smith Kline herpes zoster, herpes simplex GS
840 Gilead HIV infection, AIDS, ARC (reverse transcriptase
inhibitor) HBY097 Hoechst Marion HIV infection, Roussel AIDS, ARC
(non-nucleoside reverse transcriptase inhibitor) Hypericin VIMRx
Pharm. HIV infection, AIDS, ARC Recombinant Human Triton
Biosciences AIDS, Kaposi's Interferon Beta (Almeda, CA) sarcoma,
ARC Interferon alfa-n3 Interferon Sciences ARC, AIDS Indinavir
Merck HIV infection, AIDS, ARC, asymptomatic HIV positive, also in
combination with AZT/ddI/ddC ISIS 2922 ISIS Pharmaceuticals CMV
retinitis KNI-272 Nat'l Cancer Institute HIV-assoc. diseases
Lamivudine, 3TC Glaxo Wellcome HIV infection, AIDS, ARC (reverse
transcriptase inhibitor); also with AZT Lobucavir Bristol-Myers
Squibb CMV infection Nelfinavir Agouron HIV infection,
Pharmaceuticals AIDS, ARC (protease inhibitor) Nevirapine
Boeheringer HIV infection, Ingleheim AIDS, ARC (RT inhibitor)
Novapren Novaferon Labs, Inc. HIV inhibitor (Akron, OH) Peptide T
Peninsula Labs AIDS Octapeptide (Belmont, CA) Sequence Trisodium
Astra Pharm. CMV retinitis, HIV Phosphonoformate Products, Inc.
infection, other CMV infections PNU-140690 Pharmacia Upjohn HIV
infection, AIDS, ARC (protease inhibitor) Probucol Vyrex HIV
infection, AIDS RBC-CD4 Sheffield Med. HIV infection, Tech
(Houston, TX) AIDS, ARC Ritonavir Abbott HIV infection, AIDS, ARC
(protease inhibitor) Saquinavir Hoffmann- HIV infection, LaRoche
AIDS, ARC (protease inhibitor) Stavudine; d4T Bristol-Myers Squibb
HIV infection, AIDS, Didehydrodeoxy- ARC Thymidine Tipranavir
Boehringer Ingelheim HIV infection, AIDS, ARC (protease inhibitor)
Valaciclovir Glaxo Wellcome Genital HSV & CMV infections
Virazole Viratek/ICN asymptomatic HIV Ribavirin (Costa Mesa, CA)
positive, LAS, ARC VX-478 Vertex HIV infection, AIDS, ARC
Zalcitabine Hoffmann-LaRoche HIV infection, AIDS, ARC, with AZT
Zidovudine; AZT Glaxo Wellcome HIV infection, AIDS, ARC, Kaposi's
sarcoma, in combination with other therapies Tenofovir disoproxil,
Gilead HIV infection, fumarate salt (VIREAD .RTM.) AIDS, (reverse
transcriptase inhibitor) EMTRIVA .RTM. Gilead HIV infection,
(Emtricitabine) (FTC) AIDS, (reverse transcriptase inhibitor)
COMBIVIR .RTM. GSK HIV infection, AIDS, (reverse transcriptase
inhibitor) Abacavir succinate GSK HIV infection, (or ZIAGEN .RTM.)
AIDS, (reverse transcriptase inhibitor) REYATAZ .RTM. Bristol-Myers
Squibb HIV infection (or atazanavir) AIDs, protease inhibitor
FUZEON .RTM. Roche/Trimeris HIV infection (Enfuvirtide or T-20)
AIDs, viral Fusion inhibitor LEXIVA .RTM. GSK/Vertex HIV infection
(or Fosamprenavir calcium) AIDs, viral protease inhibitor Selzentry
Pfizer HIV infection Maraviroc; (UK 427857) AIDs, (CCR5 antagonist,
in development) Trizivir .RTM. GSK HIV infection AIDs, (three drug
combination) Sch-417690 (vicriviroc) Schering-Plough HIV infection
AIDs, (CCR5 antagonist, in development) TAK-652 Takeda HIV
infection AIDs, (CCR5 antagonist, in development) GSK 873140
GSK/ONO HIV infection (ONO-4128) AIDs, (CCR5 antagonist, in
development) Integrase Inhibitor Merck HIV infection MK-0518 AIDs
Raltegravir TRUVADA .RTM. Gilead Combination of Tenofovir
disoproxil fumarate salt (VIREAD .RTM.) and EMTRIVA .RTM.
(Emtricitabine) Integrase Inhibitor Gilead/Japan Tobacco HIV
Infection GS917/JTK-303 AIDs Elvitegravir in development Triple
drug combination Gilead/Bristol-Myers Squibb Combination of
Tenofovir ATRIPLA .RTM. disoproxil fumarate salt (VIREAD .RTM.),
EMTRIVA .RTM. (Emtricitabine), and SUSTIVA .RTM. (Efavirenz)
FESTINAVIR .RTM. Oncolys BioPharma HIV infection 4'-ethynyl-d4T BMS
AIDs in development CMX-157 Chimerix HIV infection Lipid conjugate
of AIDs nucleotide tenofovir GSK1349572 GSK HIV infection Integrase
inhibitor AIDs dolutegravir S/GSK1265744 GSK HIV infection
Integrase inhibitor AIDs IMMUNOMODULATORS AS-101 Wyeth-Ayerst AIDS
Bropirimine Pharmacia Upjohn Advanced AIDS Acemannan Carrington
Labs, Inc. AIDS, ARC (Irving, TX) CL246,738 Wyeth AIDS, Kaposi's
Lederle Labs sarcoma FP-21399 Fuki ImmunoPharm Blocks HIV fusion
with CD4+ cells Gamma Interferon Genentech ARC, in combination
w/TNF (tumor necrosis factor) Granulocyte Genetics Institute AIDS
Macrophage Colony Sandoz Stimulating Factor Granulocyte
Hoechst-Roussel AIDS Macrophage Colony Immunex Stimulating Factor
Granulocyte Schering-Plough AIDS, Macrophage Colony combination
Stimulating Factor w/AZT HIV Core Particle Rorer Seropositive HIV
Immunostimulant IL-2 Cetus AIDS, in combination Interleukin-2 w/AZT
IL-2 Hoffman-LaRoche AIDS, ARC, HIV, in
Interleukin-2 Immunex combination w/AZT IL-2 Chiron AIDS, increase
in Interleukin-2 CD4 cell counts (aldeslukin) Immune Globulin
Cutter Biological Pediatric AIDS, in Intravenous (Berkeley, CA)
combination w/AZT (human) IMREG-1 Imreg AIDS, Kaposi's (New
Orleans, LA) sarcoma, ARC, PGL IMREG-2 Imreg AIDS, Kaposi's (New
Orleans, LA) sarcoma, ARC, PGL Imuthiol Diethyl Merieux Institute
AIDS, ARC Dithio Carbamate Alpha-2 Schering Plough Kaposi's sarcoma
Interferon w/AZT, AIDS Methionine- TNI Pharmaceutical AIDS, ARC
Enkephalin (Chicago, IL) MTP-PE Ciba-Geigy Corp. Kaposi's sarcoma
Muramyl-Tripeptide Granulocyte Amgen AIDS, in combination Colony
Stimulating w/AZT Factor Remune Immune Response Immunotherapeutic
Corp. rCD4 Genentech AIDS, ARC Recombinant Soluble Human CD4
rCD4-IgG AIDS, ARC hybrids Recombinant Biogen AIDS, ARC Soluble
Human CD4 Interferon Hoffman-La Roche Kaposi's sarcoma Alfa 2a
AIDS, ARC, in combination w/AZT SK&F106528 Smith Kline HIV
infection Soluble T4 Thymopentin Immunobiology HIV infection
Research Institute (Annandale, NJ) Tumor Necrosis Genentech ARC, in
combination Factor; TNF w/gamma Interferon ANTI-INFECTIVES
Clindamycin with Pharmacia Upjohn PCP Primaquine Fluconazole Pfizer
Cryptococcal meningitis, candidiasis Pastille Squibb Corp.
Prevention of Nystatin Pastille oral candidiasis Ornidyl Merrell
Dow PCP Eflornithine Pentamidine LyphoMed PCP treatment Isethionate
(IM & IV) (Rosemont, IL) Trimethoprim Antibacterial
Trimethoprim/sulfa Antibacterial Piritrexim Burroughs Wellcome PCP
treatment Pentamidine Fisons Corporation PCP prophylaxis
Isethionate for Inhalation Spiramycin Rhone-Poulenc Cryptosporidial
diarrhea Intraconazole- Janssen-Pharm. Histoplasmosis; R51211
cryptococcal meningitis Trimetrexate Warner-Lambert PCP
Daunorubicin NeXstar, Sequus Kaposi's sarcoma Recombinant Human
Ortho Pharm. Corp. Severe anemia Erythropoietin assoc. with AZT
therapy Recombinant Human Serono AIDS-related Growth Hormone
wasting, cachexia Megestrol Acetate Bristol-Myers Squibb Treatment
of anorexia assoc. W/AIDS Testosterone Alza, Smith Kline
AIDS-related wasting Total Enteral Norwich Eaton Diarrhea and
Nutrition Pharmaceuticals malabsorption related to AIDS
Additionally, the compounds of the disclosure herein set forth may
be used in combination with HIV entry inhibitors. Examples of such
HIV entry inhibitors are discussed in DRUGS OF THE FUTURE 1999,
24(12), pp. 1355-1362; CELL, Vol. 9, pp. 243-246, Oct. 29, 1999;
and DRUG DISCOVERY TODAY, Vol. 5, No. 5, May 2000, pp. 183-194 and
Inhibitors of the entry of HIV into host cells. Meanwell, Nicholas
A.; Kadow, John F., Current Opinion in Drug Discovery &
Development (2003), 6(4), 451-461. Specifically the compounds can
be utilized in combination with attachment inhibitors, fusion
inhibitors, and chemokine receptor antagonists aimed at either the
CCR5 or CXCR4 coreceptor. HIV attachment inhibitors are also set
forth in U.S. Pat. No. 7,354,924 and U.S. Pat. No. 7,745,625.
It will be understood that the scope of combinations of the
compounds of this application with AIDS antivirals,
immunomodulators, anti-infectives, HIV entry inhibitors or vaccines
is not limited to the list in the above Table but includes, in
principle, any combination with any pharmaceutical composition
useful for the treatment of AIDS.
Preferred combinations are simultaneous or alternating treatments
with a compound of the present disclosure and an inhibitor of HIV
protease and/or a non-nucleoside inhibitor of HIV reverse
transcriptase. An optional fourth component in the combination is a
nucleoside inhibitor of HIV reverse transcriptase, such as AZT,
3TC, ddC or ddI. A preferred inhibitor of HIV protease is
REYATAZ.RTM. (active ingredient Atazanavir). Typically a dose of
300 to 600 mg is administered once a day. This may be
co-administered with a low dose of Ritonavir (50 to 500 mgs).
Another preferred inhibitor of HIV protease is KALETRA.RTM..
Another useful inhibitor of HIV protease is indinavir, which is the
sulfate salt of
N-(2(R)-hydroxy-1-(S)-indanyl)-2(R)-phenylmethyl-4-(S)-hydroxy-5-(1-(4-(3-
-pyridyl-methyl)-2(S)-N'-(t-butylcarboxamido)-piperazinyl))-pentaneamide
ethanolate, and is synthesized according to U.S. Pat. No.
5,413,999. Indinavir is generally administered at a dosage of 800
mg three times a day. Other preferred protease inhibitors are
nelfinavir and ritonavir. Another preferred inhibitor of HIV
protease is saquinavir which is administered in a dosage of 600 or
1200 mg tid. Preferred non-nucleoside inhibitors of HIV reverse
transcriptase include efavirenz. These combinations may have
unexpected effects on limiting the spread and degree of infection
of HIV. Preferred combinations include those with the following (1)
indinavir with efavirenz, and, optionally, AZT and/or 3TC and/or
ddI and/or ddC; (2) indinavir, and any of AZT and/or ddI and/or ddC
and/or 3TC, in particular, indinavir and AZT and 3TC; (3) stavudine
and 3TC and/or zidovudine; (4) tenofovir disoproxil fumarate salt
and emtricitabine.
In such combinations the compound(s) of the present invention and
other active agents may be administered separately or in
conjunction. In addition, the administration of one element may be
prior to, concurrent to, or subsequent to the administration of
other agent(s).
General Chemistry (Methods of Synthesis)
The present invention comprises compounds of Formula I, their
pharmaceutical formulations, and their use in patients suffering
from or susceptible to HIV infection. The compounds of Formula I
also include pharmaceutically acceptable salts thereof. Procedures
to construct compounds of Formula I and intermediates useful for
their synthesis are described after the Abbreviations.
Abbreviations
One or more of the following abbreviations, most of which are
conventional abbreviations well known to those skilled in the art,
may be used throughout the description of the disclosure and the
examples: RT=room temperature
BHT=2,6-di-tert-butyl-4-hydroxytoluene CSA=camphorsulfonic acid
LDA=lithium diisopropylamide KHMDS=potassium
bis(trimethylsilyl)amide SFC=supercritical fluid chromatography
Quant=quantitative TBDMS=tert-butyldimethylsilane
PTFE=polytetrafluoroethylene NMO=4-methylmorpholine-N-oxide
THF=tetrahydrofuran TLC=thin layer chromatography
DCM=dichloromethane DCE=dichloroethane TFA=trifluoroacetic acid
LCMS=liquid chromatography mass spectroscopy Prep=preparative
HPLC=high performance liquid chromatography
DAST=(diethylamino)sulfur trifluoride TEA=triethylamine
DIPEA=N,N-diisopropylethylamine
HATU=[O-(7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyluronium
hexafluorophosphate] DCC=N,N'-dicyclohexylcarbodiimide
DMAP=dimethylaminopyridine TMS=trimethylsilyl
NMR=nuclear magnetic resonance DPPA=diphenyl phosphoryl azide
AIBN=azobisisobutyronitrile TBAF=tetrabutylammonium fluoride
DMF=dimethylformamide
TBTU=O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium
tetrafluoroborate Min(s)=minute(s) h=hour(s) sat.=saturated
TEA=triethylamine EtOAc=ethyl acetate TFA=trifluoroacetic acid
PCC=pyridinium chlorochromate TLC=thin layer chromatography
Tf.sub.2NPh=(trifluoromethylsulfonyl)methanesulfonamide
dioxane=1,4-dioxane PG=protective group atm=atmosphere(s)
mol=mole(s) mmol=milimole(s) mg=milligram(s) .mu.g=microgram(s)
.mu.l=microliter(s) .mu.m=micrometer(s) mm=millimeter(s)
Rpm=revolutions per minute SM=starting material TLC=thin layer
chromatography AP=area percentage Equiv.=equivalent(s)
DMP=Dess-Martin periodinane TMSCl=trimethylsilyl chloride
TBSCl=tert-Butyldimethylsilyl chloride TBSOTf=trimethylsilyl
trifluoromethanesulfonate PhMe=toluene
PhNTf.sub.2=N-Phenyl-bis(trifluoromethanesulfonimide)
S-Phos=2-Dicyclohexylphosphino-2',6'-dimethoxybiphenyl
TFDO=methyl(trifluoromethyl)dioxirane
TEMPO=2,2,6,6-tetramethylpiperidinyloxy DI=deionized water
The terms "C-3" and "C-28" refer to certain positions of a
triterpene core as numbered in accordance with IUPAC rules
(positions depicted below with respect to an illustrative
triterpene: betulin):
##STR00013##
The same numbering is maintained when referring to the compound
series in schemes and general descriptions of methods.
##STR00014## ##STR00015##
EXAMPLES
The following examples illustrate typical syntheses of the
compounds of Formula I as described generally above. These examples
are illustrative only and are not intended to limit the disclosure
in any way. The reagents and starting materials are readily
available to one of ordinary skill in the art.
Chemistry
Typical Procedures and Characterization of Selected Examples:
Unless otherwise stated, solvents and reagents were used directly
as obtained from commercial sources, and reactions were performed
under a nitrogen atmosphere. Flash chromatography was conducted on
Silica gel 60 (0.040-0.063 particle size; EM Science supply).
.sup.1H NMR spectra were recorded on Bruker DRX-500f at 500 MHz (or
Bruker AV 400 MHz, Bruker DPX-300B, or Varian Gemini 300 at 300 MHz
as stated). The chemical shifts were reported in ppm on the .delta.
scale relative to .delta.TMS=0. The following internal references
were used for the residual protons in the following solvents:
CDCl.sub.3 (.delta..sub.H 7.26), CD.sub.3OD (.delta..sub.H 3.30),
acetic-d4 (Acetic Acid d.sub.4) (.delta..sub.H 11.6, 2.07), DMSO
mix or DMSO-D6-CDCl.sub.3 (.delta..sub.H 2.50 and 8.25) (ratio
75%:25%), and DMSO-D6 (.delta..sub.H 2.50). Standard acronyms were
employed to describe the multiplicity patterns: s (singlet), br. s
(broad singlet), d (doublet), t (triplet), q (quartet), m
(multiplet), b (broad), app (apparent). The coupling constant (J)
is in Hertz. All Liquid Chromatography (LC) data were recorded on a
Shimadzu LC-10AS liquid chromatograph using a SPD-10AV UV-Vis
detector with Mass Spectrometry (MS) data determined using a
Micromass Platform for LC in electrospray mode.
LC/MS Methods:
Method 1
Start % B=20, Final % B=100 over 2 minute gradient, hold at 100% B
Flow Rate=1 mL/min Wavelength=220 nm Solvent A=95% water, 5%
methanol, 10 mM Ammonium Actetate Solvent B=5% water, 95% methanol,
10 mM Ammonium Actetate Column=Phenomenex Luna C18, 3 .mu.m,
2.0.times.30 mm Method 2 Start % B=0, Final % B=100 over 2 minute
gradient, hold at 100 % B Flow Rate=1 mL/min Wavelength=220 nm
Solvent A=95% water, 5% methanol, 10 mM Ammonium Actetate Solvent
B=5% water, 95% methanol, 10 mM Ammonium Actetate Column=Phenomenex
Luna C18, 3 .mu.m, 2.0.times.30 mm Method 3 Start % B=30, Final %
B=100 over 4 min gradient, hold at 100% B Flow Rate=0.8 mL/min
Wavelength=220 Solvent Pair=Water-Methanol-0.1% TFA Solvent A=90%
Water-10% Methanol-0.1% TFA Solvent B=10% Water-90% Methanol-0.1%
TFA Column=PHENOMENEX-LUNA 2.0.times.50 mm 3 um Method 4 Start %
B=0, Final % B=100 over 4 min gradient, hold at 100% B Flow
Rate=0.8 mL/min Wavelength=220 Solvent Pair=Water-Methanol-0.1% TFA
Solvent A=90% Water-10% Methanol-0.1% TFA Solvent B=10% Water-90%
Methanol-0.1% TFA Column=PHENOMENEX-LUNA 2.0.times.50 mm 3 um
Method 5 Start % B=0, Final % B=100 over 4 min gradient, hold at
100% B Flow Rate=0.8 mL/min Wavelength=220 Solvent
Pair=ACN:Water:Ammonium Actetate Solvent A=5% ACN:95% Water:10 mM
Ammonium Actetate Solvent B=95% ACN:5% Water:10 mM Ammonium
Actetate Column=Phenomenex LUNA C18, 50.times.2, 3 u Prep-HPLC
Methods: Method 1 Start % B=20, Final % B=100 over 10 min gradient,
hold at 100% B Flow Rate=50 mL/min Wavelength=220 Solvent
Pair=Water-acetonitrile-TFA Solvent A=90% Water-10%
acetonitrile-0.1% TFA Solvent B=10% Water-90% acetonitrile-0.1% TFA
Column=Waters Sunfire C18, 5 .mu.m, 30.times.150 mm Method 2 Start
% B=30, Final % B=100 over 10 min gradient, hold at 100% B Flow
Rate=50 mL/min Wavelength=220 Solvent Pair=Water-acetonitrile-TFA
Solvent A=90% Water-10% acetonitrile-0.1% TFA Solvent B=10%
Water-90% acetonitrile-0.1% TFA Column=Waters Sunfire C18, 5 .mu.m,
30.times.150 mm Method 3 Start % B=20, Final % B=100 over 15 min
gradient, hold at 100% B Flow Rate=50 mL/min Wavelength=220 Solvent
Pair=Water-acetonitrile-TFA Solvent A=90% Water-10%
acetonitrile-0.1% TFA Solvent B=10% Water-90% acetonitrile-0.1% TFA
Column=Waters Xbridge Phenyl 5 .mu.m, 30.times.100 mm Method 4
Start % B=20, Final % B=100 over 8 min gradient, hold at 100% B
Flow Rate=50 mL/min Wavelength=220 Solvent
Pair=Water-acetonitrile-TFA Solvent A=90% Water-10%
acetonitrile-0.1% TFA Solvent B=10% Water-90% acetonitrile-0.1% TFA
Column=Waters Xbridge Phenyl 5 .mu.m, 30.times.100 mm Method 5
Start % B=15, Final % B=100 over 10 min gradient, hold at 100% B
for 4 min Flow Rate=50 mL/min Wavelength=220 Solvent
Pair=Water-acetonitrile-TFA Solvent A=90% Water-10%
acetonitrile-0.1% TFA Solvent B=10% Water-90% acetonitrile-0.1% TFA
Column=Waters Xbridge Phenyl 5 .mu.m, 30.times.100 mm Method 6
Start % B=10, Final % B=100 over 10 minute gradient, hold at 100% B
Flow Rate=40 mL/min Wavelength=220 nm Solvent A=10% MeOH-90%
H.sub.2O-0.1% TFA Solvent B=90% MeOH-10% H.sub.2O-0.1% TFA
Column=YMC COMBIPREP ODS 30.times.50 mm S5
Example 1
Preparation of
2-(((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-(4-carboxyphenyl)-5a,5b,8,-
8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,-
12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-3a-yl)ethynyl)benzoic
acid
##STR00016## Step 1. Preparation of tert-butyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-ethynyl-5a,5b,8,8,11a-pent-
amethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,-
13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
To a stirred solution of (diazomethyl)trimethylsilane (2 M in THF,
0.250 mL, 0.501 mmol) was added n-butyllithium (0.313 mL, 0.501
mmol) dropwise at -78.degree. C. under argon atmosphere and the
solution was stirred at -78.degree. C. for 20 min. A solution of
tert-butyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-formyl-5a,5b,8,8,11a-penta-
methyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,1-
3b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate) (prepared
as described in WO 2012106188) (300 mg, 0.501 mmol) in THF (3 mL)
was then added to the above solution at -78.degree. C. The mixture
was stirred at -78.degree. C. for two hours. The reaction was
quenched by addition of water (10 mL). The mixture was extracted
with EtOAc (3.times.20 mL). The combined organic layers were washed
with water and brine and dried over Na.sub.2SO.sub.4. After removal
of solvent, the residue was purified on a silica gel column using
0-5% ethyl acetate/hexanes as the mobile phase. The fractions
containing the desired product were combined and concentrated to
give the title compound as a white solid. (181 mg, 61%). MS: m/e
617.5 (M+23).sup.+, 5.25 min (method 1). .sup.1H NMR (400 MHz,
CHLOROFORM-d) .delta. 7.97-7.77 (m, 2H), 7.22-7.07 (m, 2H),
5.42-5.21 (m, 1H), 4.76 (s, 1H), 4.70-4.48 (m, 1H), 2.66 (d, J=5.5
Hz, 1H), 2.22-1.75 (m, 8H), 1.71 (s, 3H), 1.61 (s, 9H), 1.56-1.15
(m, 15H), 1.14-1.11 (m, 3H), 1.01 (s, 3H), 0.98 (s, 3H), 0.93 (br.
s., 6H).
Step 2. Preparation of methyl
2-(((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-(4-(tert-butoxycarbonyl)ph-
enyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a-
,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-3a-yl)et-
hynyl)benzoate
To a stirred solution of tert-butyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-ethynyl-5a,5b,8,8,11a-pent-
amethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,-
13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate (250 mg,
0.420 mmol) in anhydrous THF (25 mL) under a nitrogen atmosphere
was added methyl 2-iodobenzoate (110 mg, 0.420 mmol),
bis(triphenylphosphine)palladium(II) chloride (14.75 mg, 0.021
mmol), copper(I) iodide (8.00 mg, 0.042 mmol) and diisopropylamine
(0.089 mL, 0.630 mmol). The yellow solution mixture was heated at
60.degree. C. for 4 hours. The reaction mixture was quenched with 1
N HCl and extracted with ethyl acetate (2.times.20 mL). The
combined organic layers were washed with water and brine then dried
over sodium sulfate. The solvent was evaporated to dryness and the
residue was purified by a silica gel column to give the title
compound as a white solid (70 mg, 21%). MS: m/e 729.8 (M+H).sup.+,
5.501 min (method 1). .sup.1H NMR (400 MHz, CHLOROFORM-d) .delta.
7.97-7.81 (m, 3H), 7.57 (dd, J=7.8, 1.0 Hz, 1H), 7.46 (td, J=7.5,
1.3 Hz, 1H), 7.35 (td, J=7.7, 1.3 Hz, 1H), 7.25-7.10 (m, 2H), 5.29
(d, J=4.8 Hz, 1H), 4.91-4.73 (m, 1H), 4.69-4.56 (m, 1H), 3.96 (s,
3H), 3.07-2.61 (m, 1H), 2.46-1.93 (m, 5H), 1.89-1.66 (m, 3H), 1.74
(s, 3H), 1.61 (s, 9H), 1.57-1.21 (m, 14H), 1.14 (s, 3H), 1.02 (s,
3H), 1.00-0.97 (m, 3H), 0.94 (d, J=3.0 Hz, 6H).
Step 3: To a solution of methyl
2-(((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-(4-(tert-butoxycarbonyl)ph-
enyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a-
,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-3a-yl)et-
hynyl)benzoate (70 mg, 0.096 mmol) in dioxane (2 mL) and MeOH (1
mL) was added 1N NaOH (1 mL, 1 mmol). The mixture was stirred at
85.degree. C. for 15 h. The resulted solution was purified by prep
HPLC (method 1) to give
2-(((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-(4-carboxyphenyl)-5a,-
5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a-
,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-3a-yl)ethynyl)ben-
zoic acid as a white solid (6.0 mg, 9.5%). MS: m/e 659.7
(M+H).sup.+, 2.50 min (method 2). .sup.1H NMR (400 MHz,
METHANOL-d.sub.4) .delta. 7.92 (d, J=8.3 Hz, 2H), 7.77 (dd, J=7.8,
1.0 Hz, 1H), 7.54-7.49 (m, 1H), 7.44 (td, J=7.5, 1.5 Hz, 1H),
7.39-7.31 (m, 1H), 7.22 (d, J=8.3 Hz, 2H), 5.31 (dd, J=6.1, 1.6 Hz,
1H), 4.79 (d, J=2.3 Hz, 1H), 4.63 (dd, J=2.1, 1.4 Hz, 1H), 2.83
(td, J=11.0, 5.4 Hz, 1H), 2.41-2.11 (m, 4H), 2.04-1.92 (m, 2H),
1.84 (d, J=11.3 Hz, 1H), 1.78-1.69 (m, 1H), 1.74 (s, 3H), 1.65-1.21
(m, 14H), 1.18 (s, 3H), 1.06 (s, 3H), 1.04 (s, 3H), 0.98 (s, 3H),
0.96 (s, 3H).
Example 2
Preparation of 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13
aR,13bR)-3a-((2-(1H-tetrazol-5-yl)thiophen-3-yl)ethynyl)-5a,5b,8,8,11a-pe-
ntamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13-
a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoic acid
##STR00017## Step 1. Preparation of tert-butyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((2-cyanothiophen-3-yl)eth-
ynyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a-
,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)ben-
zoate
The title compound was prepared in 71% yield following the
procedure described above in step 2 of the preparation of
4-((1R,3aR,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(2-(1,1-dioxidothiomorphol-
ino)ethyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6-
,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-y-
l)benzoic acid, using 3-bromothiophene-2-carbonitrile as the
reactant. MS: m/e 646.6 (M+H-56).sup.+, 4.68 min (method 2).
.sup.1H NMR (400 MHz, CHLOROFORM-d) .delta. 7.88 (d, J=8.3 Hz, 2H),
7.64-7.46 (m, 1H), 7.16 (d, J=8.0 Hz, 2H), 7.13-6.99 (m, 1H), 5.27
(d, J=4.8 Hz, 1H), 4.83-4.72 (m, 1H), 4.68-4.55 (m, 1H), 2.96-2.65
(m, 1H), 2.33-2.20 (m, 1H), 2.14-1.73 (m, 6H), 1.72-1.63 (m, 1H),
1.71 (s, 3H), 1.62-1.57 (m, 9H), 1.55-1.34 (m, 8H), 1.33-1.18 (m,
5H), 1.15-1.04 (m, 1H), 1.00 (d, J=3.3 Hz, 3H), 0.99-0.95 (m, 6H),
0.91 (s, 6H).
Step 2. Preparation of tert-butyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((2-(1H-tetrazol-5-yl)thio-
phen-3-yl)ethynyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5-
,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chr-
ysen-9-yl)benzoate
To a resealable pressure tube was added tert-butyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((2-cyanothiophen-3-yl)eth-
ynyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a-
,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)ben-
zoate (251 mg, 0.358 mmol) and azidotributylstannane (313 mg, 0.941
mmol) in toluene (1 mL) under nitrogen. The pressure tube was
sealed and warmed to 130.degree. C. overnight. The crude reaction
mixture was evaporated to dryness, washed with water (10 mL)
extracted with EtOAc (2.times.10 mL). The organic layers were
combined and dried over sodium sulfate. The solvent was evaporated
to dryness and the residue was purified in a silica gel column to
give titled compound as a white solid (170 mg, 63.8%). MS: m/e
745.87 (M+H).sup.+, 3.05 min (method 2). .sup.1H NMR (400 MHz,
CHLOROFORM-d) .delta. 7.90 (d, J=8.3 Hz, 2H), 7.56 (d, J=5.0 Hz,
1H), 7.23 (d, J=5.0 Hz, 1H), 7.20-7.13 (m, 2H), 5.29 (dd, J=6.1,
1.6 Hz, 1H), 4.78 (d, J=1.5 Hz, 1H), 4.67 (s, 1H), 2.68 (td,
J=11.0, 5.6 Hz, 1H), 2.29-1.95 (m, 3H), 1.86-1.69 (m, 2H), 1.74 (s,
3H), 1.69-1.58 (m, 4H), 1.61 (s, 9H), 1.57-1.14 (m, 14H), 1.11 (s,
3H), 1.04 (s, 3H), 0.99 (s, 3H), 0.95-0.93 (m, 6H).
Step 3:
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((2-(1H-tetrazol-5-
-yl)thiophen-3-yl)ethynyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,-
3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopen-
ta[a]chrysen-9-yl)benzoic acid (solid, 25.4% yield) was obtained
following the method described above in step 3 of the preparation
of 2-(((1R,3aS,5aR,5bR,7aR,11aS,11bR,13
aR,13bR)-9-(4-carboxyphenyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-
-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclo-
penta[a]chrysen-3a-yl)ethynyl)benzoic acid, using tert-butyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13
aR,13bR)-3a-((2-(1H-tetrazol-5-yl)thiophen-3-yl)ethynyl)-5a,5b,8,8,11a-pe-
ntamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13-
a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate as the
reactant. MS: m/e 689.45 (M+H-56).sup.+, 3.046 min (method 2).
.sup.1H NMR (400 MHz, CHLOROFORM-d) .delta. 9.67 (s., 1H), 8.02 (d,
J=8.3 Hz, 2H), 7.62 (d, J=5.0 Hz, 1H), 7.38-7.16 (m, 3H), 5.33 (d,
J=4.5 Hz, 1H), 4.79 (s, 1H), 4.69 (s, 1H), 2.67 (td, J=10.9, 5.8
Hz, 1H), 2.35-1.79 (m, 8H), 1.75 (s, 3H), 1.72-1.14 (m, 15H), 1.12
(s, 3H), 1.06 (s, 3H), 1.00 (s, 3H), 0.96 (s, 6H).
Example 3
Preparation of
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a--
(1,3,4-oxadiazol-2-yl)-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a-
,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoic
acid
##STR00018## ##STR00019## Step 1. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(chlorocarbonyl)-5a,5b,8,8-
,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,1-
2,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate.
To a slurry of
(1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-(4-(methoxycarbonyl)phenyl)-5a-
,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11-
a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysene-3a-carboxylic
acid (400 mg, 0.698 mmol) at 0.degree. C. in DCM (15 mL was added
oxalyl chloride (0.177 mL, 2.095 mmol) and N,N-dimethylformamide
(0.054 mL, 0.698 mmol). The cold bath was removed and reaction was
stirred at rt. Gas evolved vigorously and reaction became a clear
and homogeneous solution. After 4 h, a small aliquot was taken and
quenched with MeOH and TLC (9:1 hex:EtOAc) showed reaction was
complete. The reaction was concentrated and dried in vacuo to give
the title compound (410 mg, 99% yield) as an off-white solid. The
material was used in the next step without further
purification.
Step 2. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(2-formylhydrazinecarbonyl-
)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,1-
1,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoat-
e.
To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(chlorocarbonyl)-5a,5b,8,8-
,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,1-
2,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(110 mg, 0.186 mmol) in DCM (2 mL) was added
N,N-diisopropylethylamine (0.130 mL, 0.744 mmol) and formic acid
hydrazide (33.5 mg, 0.558 mmol) and the mixture was stirred at rt
overnight. After 16 h, the reaction was concentrated. The crude
material was purified by reverse phase prep-HPLC using HPLC method
1 to give the title compound (86.4 mg, 76% yield) as a white solid.
LC/MS: m/e 614.0 (M+H).sup.+, 5.58 min (method 3). .sup.1H NMR (400
MHz, CHLOROFORM-d) .delta. 9.20 (br. s., 1H), 7.93 (d, J=8.3 Hz,
2H), 7.20 (d, J=8.3 Hz, 2H), 5.29 (d, J=4.6 Hz, 1H), 4.78 (s, 1H),
4.66 (s, 1H), 3.91 (s, 3H), 3.24 (s, 4H), 2.95 (td, J=11.0, 5.4 Hz,
1H), 2.37 (td, J=12.2, 3.2 Hz, 1H), 2.24-2.05 (m, 2H), 2.02-1.93
(m, 1H), 1.92-1.75 (m, 3H), 1.73 (s, 3H), 1.71-1.62 (m, 2H),
1.58-1.33 (m, 9H), 1.30-1.18 (m, 2H), 1.09 (s, 1H), 1.03 (s, 2H),
0.98 (s, 3H), 0.95 (s, 3H), 0.93 (s, 5H).
Step 3. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a--
(1,3,4-oxadiazol-2-yl)-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a-
,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate.
To a slurry of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(2-formylhydrazinecarbonyl-
)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,1-
1,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoat-
e (83 mg, 0.135 mmol) and N,N-diisopropylethylamine (0.188 mL,
1.080 mmol) in acetonitrile (2 mL) was added p-toluenesulfonyl
chloride (129 mg, 0.675 mmol). The mixture was treated with DCM (1
mL) and the reaction became a homogeneous solution which was
stirred at rt for 16 h. The reaction was concentrated and purified
by reverse phase prep-HPLC using HPLC method 2 and dried in vacuo
to give the title compound (51.3 mg, 58.6% yield) as a white solid.
LC/MS: m/e 597.3 (M+H).sup.+, 6.70 min (method 3). .sup.1H NMR (400
MHz, CHLOROFORM-d) .delta. 8.38 (s, 1H), 7.93 (d, J=8.3 Hz, 2H),
7.20 (d, J=8.3 Hz, 2H), 5.29 (dd, J=6.4, 1.7 Hz, 1H), 4.81 (d,
J=1.7 Hz, 1H), 4.69-4.63 (m, 1H), 3.91 (s, 3H), 3.15 (td, J=11.1,
5.1 Hz, 1H), 2.46-2.32 (m, 2H), 2.11 (dd, J=17.1, 6.4 Hz, 1H),
2.01-1.91 (m, 2H), 1.90-1.78 (m, 2H), 1.75 (s, 3H), 1.73-1.62 (m,
3H), 1.50-1.31 (m, 9H), 1.25-1.18 (m, 2H), 1.16-1.09 (m, 1H), 1.06
(s, 3H), 0.96 (s, 3H), 0.92 (s, 6H), 0.86 (s, 3H).
Step 4: To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a--
(1,3,4-oxadiazol-2-yl)-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a-
,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(48 mg, 0.080 mmol) in THF (1 mL) and MeOH (0.5 mL) was added a
solution of 1N lithium hydroxide (0.241 mL, 0.241 mmol). The
reaction mixture was stirred at 75.degree. C. After 1 h, the
reaction was cooled to rt and purified by reverse phase prep-HPLC
using HPLC method 2 to give
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a--
(1,3,4-oxadiazol-2-yl)-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a-
,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoic
acid (21.8 mg, 43.3% yield) as a white solid. LC/MS: m/e 583.3
(M+H).sup.+, 5.38 min (method 3). .sup.1H NMR (400 MHz,
CHLOROFORM-d) .delta. 8.39 (s, 1H), 8.00 (d, J=8.3 Hz, 2H), 7.23
(d, J=8.3 Hz, 2H), 5.31 (d, J=4.6 Hz, 1H), 4.81 (d, J=1.5 Hz, 1H),
4.66 (s, 1H), 3.16 (td, J=11.1, 5.1 Hz, 1H), 2.46-2.32 (m, 3H),
2.12 (dd, J=17.1, 6.4 Hz, 1H), 1.97-1.89 (m, 2H), 1.84-1.79 (m,
1H), 1.73-1.68 (m, 2H), 1.68-1.60 (m, 2H), 1.55-1.46 (m, 3H), 1.44
(s, 3H), 1.40-1.31 (m, 4H), 1.25-1.19 (m, 2H), 1.14 (d, J=6.1 Hz,
1H), 1.06 (s, 3H), 1.00 (d, J=11.0 Hz, 1H), 0.96 (s, 3H), 0.93 (s,
6H), 0.86 (s, 3H). .sup.13C NMR (101 MHz, CHLOROFORM-d) .delta.
170.5, 170.1, 152.3, 149.8, 149.6, 146.2, 130.2, 129.1, 126.8,
125.5, 124.2, 110.2, 77.2, 52.9, 50.5, 49.8, 49.5, 46.8, 42.6,
41.7, 40.6, 38.2, 37.9, 37.5, 36.3, 33.6, 32.7, 30.3, 30.2, 29.4,
28.9, 25.4, 21.2, 21.0, 19.7, 19.5, 16.4, 15.6, 14.8.
Example 4
Preparation of 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13
aR,13bR)-3a-(5-((dimethylamino)methyl)-1,3,4-oxadiazol-2-yl)-5a,5b,8,8,11-
a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,1-
3,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoic
acid
##STR00020## ##STR00021## Step 1. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(hydrazinecarbonyl)-5a,5b,-
8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11-
b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate.
To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(chlorocarbonyl)-5a,5b,8,8-
,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,1-
2,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(400 mg, 0.677 mmol) and N,N-diisopropylethylamine (0.354 mL, 2.030
mmol) was added quickly hydrazine monohydrate (0.670 mL, 13.53
mmol). The resulting cloudy reaction mixture was stirred at rt.
After 1 h, the reaction was concentrated, the resulting white solid
was dissolved in DCM (50 mL) and washed with 1N HCl (15 mL). The
resulting emulsion mixture was treated with brine, shaken, and the
layers were separated. The aqueous layer was extracted with DCM (50
mL). The combined organic layers were washed with brine, dried over
MgSO.sub.4, filtered, concentrated and dried in vacuo to give the
title compound (358 mg, 90% yield) as a white solid. LC/MS: m/e
587.3 (M+H).sup.+, 4.65 min (method 3).
.sup.1H NMR (400 MHz, CHLOROFORM-d) .delta. 7.96-7.90 (m, 2H), 7.20
(d, J=8.3 Hz, 2H), 6.88 (s, 1H), 5.32-5.27 (m, 1H), 4.77 (d, J=2.0
Hz, 1H), 4.62 (t, J=1.7 Hz, 1H), 3.91 (s, 3H), 3.12 (td, J=10.8,
4.0 Hz, 1H), 2.53-2.37 (m, 1H), 2.12 (dd, J=17.1, 6.4 Hz, 1H), 1.95
(d, J=13.2 Hz, 2H), 1.80-1.73 (m, 2H), 1.71 (s, 3H), 1.69-1.61 (m,
2H), 1.59-1.52 (m, 2H), 1.51-1.36 (m, 9H), 1.33 (dd, J=12.1, 4.3
Hz, 1H), 1.22 (d, J=12.5 Hz, 2H), 1.01 (s, 3H), 1.00 (s, 3H), 0.98
(s, 3H), 0.93 (s, 3H), 0.93 (s, 3H). .sup.13C NMR (101 MHz,
CHLOROFORM-d) .delta. 177.2, 167.2, 150.6, 148.7, 146.2, 130.1,
128.5, 127.9, 124.1, 109.6, 77.2, 55.0, 52.9, 52.0, 50.3, 49.6,
46.8, 42.4, 41.7, 40.6, 38.3, 38.1, 37.5, 36.3, 33.7, 33.3, 30.8,
29.4, 25.7, 21.3, 21.0, 19.8, 19.5, 16.4, 15.9, 14.7.
Step 2. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(2-(2-(dimethylamino)acety-
l)hydrazinecarbonyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4-
,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]c-
hrysen-9-yl)benzoate.
To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(hydrazinecarbonyl)-5a,5b,-
8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11-
b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(102 mg, 0.174 mmol) in DCM (2 mL) was added
N,N-diisopropylethylamine (0.121 mL, 0.695 mmol) and
dimethylaminoacetyl chloride hydrochloride (30.2 mg, 0.191 mmol).
The resulting brown reaction mixture was stirred at rt. After 2h,
the reaction mixture was concentrated and dried under vacuo to give
the title compound as an off-white foam. The material was used in
the next step without further purification. LC/MS: m/e 672.4
(M+H).sup.+, 4.63 min (method 3).
Step 3. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(5-((dimethylamino)methyl)-
-1,3,4-oxadiazol-2-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a-
,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a-
]chrysen-9-yl)benzoate.
To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(2-(2-(dimethylamino)acety-
l)hydrazinecarbonyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4-
,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]c-
hrysen-9-yl)benzoate (33 mg, 0.049 mmol) and
N,N-diisopropylethylamine (0.068 mL, 0.393 mmol) in acetonitrile (1
mL) was added p-toluenesulfonyl chloride (46.8 mg, 0.246 mmol). The
reaction became a homogeneous solution and was stirred at rt. After
17 h, the reaction mixture was diluted with THF (0.5 mL) and
purified by reverse phase prep-HPLC using HPLC method 3 and dried
in vacuo to give methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(5-((dimethylamino)methyl)-
-1,3,4-oxadiazol-2-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a-
,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a-
]chrysen-9-yl)benzoate, TFA (17.7 mg, 0.022 mmol, 45.5% yield) as
an off white solid. LC/MS: m/e 654.4 (M+H).sup.+, 4.76 min (method
4). .sup.1H NMR (400 MHz, CHLOROFORM-d) .delta. 7.92 (d, J=8.3 Hz,
2H), 7.19 (d, J=8.3 Hz, 2H), 5.29 (d, J=4.6 Hz, 1H), 4.80 (s, 1H),
4.67 (s, 1H), 4.50 (br. s., 2H), 3.91 (s, 3H), 3.13 (td, J=11.0,
5.1 Hz, 1H), 2.91 (s, 6H), 2.39 (td, J=12.1, 3.4 Hz, 1H), 2.31 (d,
J=11.2 Hz, 1H), 2.11 (dd, J=17.1, 6.4 Hz, 1H), 1.99-1.88 (m, 2H),
1.81 (d, J=10.0 Hz, 2H), 1.74 (s, 3H), 1.71-1.63 (m, 2H), 1.56-1.35
(m, 8H), 1.31 (dd, J=12.2, 3.9 Hz, 1H), 1.27-1.18 (m, 3H), 1.12
(dd, J=12.5, 3.7 Hz, 1H), 1.05 (s, 3H), 0.95 (s, 3H), 0.92 (s, 3H),
0.91 (s, 3H), 0.84 (s, 3H). .sup.13C NMR (101 MHz, CHLOROFORM-d)
.delta. 172.5, 167.2, 149.4, 148.7, 146.2, 130.0, 128.5, 127.9,
124.0, 110.3, 77.22-77.17, 52.8, 52.0, 50.9, 49.7, 49.4, 46.7,
42.5, 42.4, 41.7, 40.6, 38.2, 37.7, 37.5, 36.2, 33.5, 32.4, 30.0,
29.4, 28.9, 25.4, 21.2, 21.0, 19.7, 19.4, 16.4, 15.6, 14.8.
Step 4: To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(5-((dimethylamino)methyl)-
-1,3,4-oxadiazol-2-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a-
,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a-
]chrysen-9-yl)benzoate, TFA (54.7 mg, 0.071 mmol) in THF (1 mL) and
MeOH (0.25 mL) was added a solution of 3N lithium hydroxide (0.083
mL, 0.249 mmol). The reaction was stirred at 75.degree. C. After 1
h, the reaction was cooled to rt and purified by reverse phase
prep-HPLC using HPLC method 4 and dried under vacuo to give
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(5-((dimethylamino)methyl)-
-1,3,4-oxadiazol-2-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a-
,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a-
]chrysen-9-yl)benzoic acid, TFA (45.5 mg, 0.057 mmol, 80% yield) as
a white solid. LC/MS: m/e 640.4 (M+H).sup.+, 4.33 min (method 3).
.sup.1H NMR (400 MHz, 1:1 CDCl.sub.3:METHANOL-d.sub.4) .delta. 7.89
(d, J=8.3 Hz, 2H), 7.17 (d, J=8.3 Hz, 2H), 5.27 (dd, J=6.2, 1.6 Hz,
1H), 4.77 (d, J=1.5 Hz, 1H), 4.53 (s, 2H), 3.09 (td, J=11.0, 5.1
Hz, 1H), 2.90 (s, 6H), 2.39 (td, J=12.1, 3.4 Hz, 1H), 2.30 (d,
J=13.4 Hz, 1H), 2.10 (dd, J=17.1, 6.4 Hz, 1H), 2.00-1.89 (m, 2H),
1.84-1.75 (m, 2H), 1.73 (s, 3H), 1.71-1.64 (m, 2H), 1.56-1.35 (m,
8H), 1.33-1.18 (m, 4H), 1.16-1.09 (m, 1H), 1.06 (s, 3H), 0.95 (s,
3H), 0.90 (s, 6H), 0.85 (s, 3H).
Example 5
Preparation of
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-1-(-
prop-1-en-2-yl)-3a-(1H-1,2,4-triazol-3-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11-
a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoic
acid
##STR00022## ##STR00023## Step 1. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-carbamoyl-5a,5b,8,8,11a-pe-
ntamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13-
a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate.
To a cloudy solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(chlorocarbonyl)-5a,5b,8,8-
,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,1-
2,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(300 mg, 0.507 mmol) in 1,4-dioxane (20 mL) was added ammonium
hydroxide (2.305 mL, 17.76 mmol) and the mixture was stirred at rt
overnight. The reaction was concentrated to dryness. The white
residue formed was triturated with H.sub.2O (15 mL), filtered,
washed with H.sub.2O (2.times.15 mL) and dried in a vacuum oven at
50.degree. C. to give the title compound (290 mg, 100% yield) as a
white solid. LC/MS: m/e 572.3 (M+H).sup.+, 6.09 min (method 3).
.sup.1H NMR (400 MHz, CHLOROFORM-d) .delta. 7.93 (d, J=8.1 Hz, 2H),
7.20 (d, J=8.1 Hz, 2H), 5.51 (br. s., 1H), 5.30 (d, J=4.9 Hz, 1H),
5.18 (br. s., 1H), 4.77 (br. s., 1H), 4.62 (br. s., 1H), 3.91 (s,
3H), 3.12 (td, J=11.0, 4.2 Hz, 1H), 2.61-2.46 (m, 1H), 2.12 (dd,
J=17.2, 6.2 Hz, 1H), 2.07-1.99 (m, 1H), 1.95 (d, J=12.7 Hz, 1H),
1.83 (dd, J=11.9, 7.9 Hz, 1H), 1.76 (br. s., 1H), 1.71 (s, 3H),
1.67-1.61 (m, 3H), 1.52 (d, J=10.5 Hz, 3H), 1.44 (d, J=7.8 Hz, 4H),
1.39 (br. s., 2H), 1.24 (d, J=10.8 Hz, 2H), 1.04 (s, 3H), 1.02 (s,
3H), 0.99 (s, 3H), 0.93 (s, 6H).
Step 2. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((E)-((dimethylamino)methy-
lene)carbamoyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a-
,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chryse-
n-9-yl)benzoate and methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(formylcarbamoyl)-5a,5b,8,-
8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,-
12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate.
To a slurry of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-carbamoyl-5a,5b,8,8,11a-pe-
ntamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13-
a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate (0.285 g,
0.498 mmol) in THF (5 mL) in a medium pressure tube was added
N,N-dimethylformamidedimethylacetal (1.057 mL, 7.48 mmol). The
resulting slurry was stirred at 85.degree. C. The reaction mixture
turned clear and became homogeneous after 5 mins at 85.degree. C.
After 18 h, the reaction was concentrated to a white foam material
which was purified by flash column chromatography, using 4:1
hex:EtOAc as the mobile phase to give two products. Product one,
top spot by TLC (R.sub.f=0.82 in 2:1 hex:EtOAc) was identified as:
methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(formylcarbamoyl)-5a,5b,8,-
8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,-
12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(119.2 mg, 39.9% yield, white solid). LC/MS: m/e 598.5 (M-H).sup.-,
5.07 min (method 5). .sup.1H NMR (400 MHz, CHLOROFORM-d) .delta.
9.22 (d, J=9.8 Hz, 1H), 8.36 (d, J=9.8 Hz, 1H), 7.98-7.92 (m, 2H),
7.22 (d, J=8.6 Hz, 2H), 5.31 (d, J=2.0 Hz, 1H), 4.79 (d, J=1.7 Hz,
1H), 4.66 (d, J=1.5 Hz, 1H), 3.93 (s, 3H), 3.06 (td, J=11.0, 4.4
Hz, 1H), 2.59-2.47 (m, 1H), 2.14 (dd, J=17.1, 6.4 Hz, 1H),
2.03-1.91 (m, 2H), 1.85 (dd, J=12.1, 7.7 Hz, 1H), 1.81-1.75 (m,
1H), 1.72 (s, 4H), 1.59 (s, 4H), 1.55-1.37 (m, 9H), 1.35-1.29 (m,
2H), 1.27-1.19 (m, 1H), 1.04 (s, 3H), 1.02 (s, 3H), 1.01 (s, 3H),
0.95 (s, 3H), 0.94 (s, 3H). .sup.13C NMR (101 MHz, CHLOROFORM-d)
.delta. 176.1, 167.2, 163.1, 149.9, 148.7, 146.3, 130.0, 128.5,
127.9, 124.0, 110.0, 77.2, 56.8, 53.4, 52.9, 52.0, 49.6, 46.2,
42.5, 41.8, 40.6, 37.6, 37.5, 36.8, 36.3, 33.6, 32.2, 30.3, 29.5,
29.4, 25.7, 21.3, 21.0, 19.8, 19.4, 16.5, 15.8, 14.6. Second
product, bottom spot by TLC (R.sub.f=0.55 in 2:1 hex:EtOAc) was
identified as: methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((E)-((dimethylamino)methy-
lene)carbamoyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a-
,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chryse-
n-9-yl)benzoate (150.2 mg, 48.1% yield, white foam). LC/MS: m/e
627.4 (M+H).sup.+, 6.00 min (method 5). .sup.1H NMR (400 MHz,
CHLOROFORM-d) .delta. 8.36 (s, 1H), 7.97-7.91 (m, 2H), 7.22 (d,
J=8.3 Hz, 2H), 5.32-5.29 (m, 1H), 4.77 (d, J=2.4 Hz, 1H), 4.66 (s,
1H), 4.61 (dd, J=2.4, 1.5 Hz, 1H), 3.93 (s, 3H), 3.21-3.13 (m, 1H),
3.12 (s, 3H), 3.07 (s, 3H), 2.64-2.54 (m, 1H), 2.50-2.43 (m, 1H),
2.13 (dd, J=17.1, 6.6 Hz, 1H), 2.01 (dd, J=11.0, 8.3 Hz, 1H),
1.95-1.85 (m, 1H), 1.82-1.75 (m, 1H), 1.73 (s, 4H), 1.50-1.36 (m,
10H), 1.26-1.21 (m, 1H), 1.18-1.13 (m, 1H), 1.10-1.10 (m, 1H), 1.08
(br. s., 1H), 1.03 (s, 3H), 1.00 (s, 3H), 0.99 (s, 3H), 0.94 (s,
6H).
Step 3. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-1-(-
prop-1-en-2-yl)-3a-(1H-1,2,4-triazol-3-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11-
a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate.
To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(formylcarbamoyl)-5a,5b,8,-
8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,-
12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(115 mg, 0.192 mmol) in glacial acetic acid (2mL) and THF (1 mL)
was added hydrazine hydrate (0.097 mL, 1.917 mmol). The resulting
slurry was stirred at 90.degree. C. After 3 h the reaction was
cooled to rt and concentrated. The resulting residue was triturated
with MeOH, filtered and washed with MeOH then dried under vacuo to
give the title compound (104.3 mg, 0.175 mmol, 91% yield) as a
white solid. LC/MS: m/e 596.3 (M+H).sup.+, 5.28 min (method 3).
.sup.1H NMR (400 MHz, CHLOROFORM-d) .delta. 8.05 (s, 1H), 7.93 (d,
J=7.8 Hz, 2H), 7.19 (d, J=8.1 Hz, 2H), 5.29 (d, J=4.9 Hz, 1H), 4.82
(br. s., 1H), 4.66 (br. s., 1H), 3.91 (s, 3H), 3.18 (d, J=10.0 Hz,
1H), 2.43 (t, J=10.6 Hz, 1H), 2.32 (d, J=12.7 Hz, 1H), 2.17-2.05
(m, 2H), 1.94-1.82 (m, 3H), 1.77 (s, 3H), 1.71-1.62 (m, 3H),
1.53-1.30 (m, 10H), 1.17 (d, J=14.4 Hz, 3H), 1.06 (s, 3H), 0.95
(br. s., 3H), 0.92 (br. s., 6H), 0.78 (s, 3H).
The title compound was also obtained in the following manner:
To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((E)-((dimethylamino)methy-
lene)carbamoyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a-
,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chryse-
n-9-yl)benzoate (145 mg, 0.231 mmol) in glacial acetic acid (3 mL)
was added hydrazine hydrate (0.058 mL, 1.156 mmol). The resulting
slurry was stirred at 90.degree. C. After 3 h, the reaction was let
cooled to rt and concentrated. The residue was triturated with
MeOH, filtered, washed with MeOH and dried in vacuo to give the
title compound (91.2 mg, 66.2% yield) as white solid. The residue
from the filtrate was purified by reverse phase prep-HPLC using
HPLC method 2 and dried to give more of the title compound (31.4
mg, 22.78% yield) as a white solid. LC/MS: m/e 596.4 (M+H).sup.+,
5.26 min (method 3). .sup.1H NMR (400 MHz, CHLOROFORM-d) .delta.
8.84 (br. s., 1H), 7.93 (d, J=8.6 Hz, 2H), 7.19 (d, J=8.3 Hz, 2H),
5.37-5.24 (m, 1H), 4.81 (s, 1H), 4.68 (s, 1H), 3.92 (s, 3H), 3.12
(dd, J=10.8, 6.1 Hz, 1H), 2.55-2.42 (m, 1H), 2.35 (d, J=13.2 Hz,
1H), 2.18-2.06 (m, 1H), 2.01-1.90 (m, 2H), 1.83 (d, J=13.2 Hz, 2H),
1.76 (s, 3H), 1.73-1.64 (m, 3H), 1.54-1.30 (m, 8H), 1.25-1.09 (m,
4H), 1.06 (s, 3H), 0.96 (s, 3H), 0.92 (s, 3H), 0.91 (s, 3H), 0.80
(s, 3H).
Step 4: To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-1-(-
prop-1-en-2-yl)-3a-(1H-1,2,4-triazol-3-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11-
a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(192 mg, 0.322 mmol) in THF (3 mL) and MeOH (1 mL) was added a
solution of 3N lithium hydroxide (0.322 mL, 0.967 mmol). The
reaction was stirred at 75.degree. C. After 1.5 h the reaction was
cooled to rt and concentrated to a viscous oil. The crude material
was purified by reverse phase prep-HPLC using HPLC method 1 and
dried in vacuo to give
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-1-(-
prop-1-en-2-yl)-3a-(1H-1,2,4-triazol-3-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11-
a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoic
acid (134.4 mg, 68.8% yield) as a white solid. LC/MS: m/e 582.3
(M+H).sup.+, 4.68 min (method 3). .sup.1H NMR (400 MHz, 1:1 CDL3:
METHANOL-d.sub.4) .delta. 8.57 (s, 1H), 7.89 (d, J=8.3 Hz, 2H),
7.17 (d, J=8.3 Hz, 2H), 5.26 (d, J=4.6 Hz, 1H), 4.77 (d, J=1.2 Hz,
1H), 4.62 (d, J=1.5 Hz, 1H), 3.15 (td, J=10.6, 4.5 Hz, 1H), 2.55
(td, J=12.2, 3.3 Hz, 1H), 2.28 (d, J=13.7 Hz, 1H), 2.10 (dd,
J=17.1, 6.4 Hz, 1H), 1.90 (t, J=11.5 Hz, 1H), 1.86-1.75 (m, 3H),
1.73 (s, 3H), 1.70-1.62 (m, 3H), 1.52-1.28 (m, 8H), 1.25-1.18 (m,
1H), 1.17-1.08 (m, 3H), 1.04 (s, 3H), 0.95 (s, 3H), 0.89 (s, 6H),
0.78 (s, 3H). .sup.13C NMR (101 MHz, 1:1
CDCl.sub.3:METHANOL-d.sub.4) .delta. 169.8, 163.0, 150.9, 149.5,
147.1, 145.6, 130.7, 129.4, 129.0, 124.7, 110.4, 78.5, 53.6, 50.8,
50.6, 50.3, 47.3, 43.3, 42.5, 41.3, 40.1, 38.4, 38.1, 37.0, 34.6,
34.3, 30.9, 29.9, 29.4, 26.3, 22.0, 21.5, 20.4, 19.8, 16.9, 16.0,
15.3.
Example 6
Preparation of
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(1-(2-(1,1-dioxidothiomorp-
holino)ethyl)-1H-1,2,4-triazol-3-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-e-
n-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1-
H-cyclopenta[a]chrysen-9-yl)benzoic acid
##STR00024## Step 1. Preparation of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(1-(2-(1,1-dioxidothiomorp-
holino)ethyl)-1H-1,2,4-triazol-3-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-e-
n-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1-
H-cyclopenta[a]chrysen-9-yl)benzoate, TFA.
Methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamet-
hyl-1-(prop-1-en-2-yl)-3a-(1H-1,2,4-triazol-3-yl)-2,3,3a,4,5,5a,5b,6,7,7a,-
8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benz-
oate (28 mg, 0.047 mmol), 4-(2-chloroethyl)thiomorpholine
1,1-dioxide (18.58 mg, 0.094 mmol), phosphoric acid, potassium salt
(49.9 mg, 0.235 mmol), and potassium iodide (31.2 mg, 0.188 mmol)
were combined in a medium pressure tube and charged with
acetonitrile (2 mL). The resulting slurry was stirred at
120.degree. C. After 16 h, LC/MS showed starting material left thus
was added more 4-(2-chloroethyl)thiomorpholine 1,1-dioxide (18.58
mg, 0.094 mmol) and the mixture was further stirred continued at
120.degree. C. for another 8 h. The reaction was cooled to rt,
filtered, washed with DCM and concentrated to a brown solid. The
crude material was purified by reverse phase prep-HPLC using HPLC
method 1 and dried under vacuo to give methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(1-(2-(1,1-dioxidothiomorp-
holino)ethyl)-1H-1,2,4-triazol-3-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-e-
n-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1-
H-cyclopenta[a]chrysen-9-yl)benzoate, TFA (12.1 mg, 46% based on
rec. sm) as a glassy solid. LC/MS: m/e 757.4 (M+H).sup.+, 5.50 min
(method 3). .sup.1H NMR (400 MHz, CHLOROFORM-d) .delta. 9.61 (br.
s., 1H), 8.46 (br. s., 2H), 7.93 (d, J=8.3 Hz, 2H), 7.19 (d, J=8.3
Hz, 2H), 5.32-5.27 (m, 1H), 4.76 (s, 1H), 4.67 (s, 1H), 4.46 (t,
J=5.4 Hz, 2H), 3.91 (s, 3H), 3.22-3.13 (m, 2H), 3.13-3.05 (m, 7H),
3.05-2.94 (m, 1H), 2.59-2.46 (m, 1H), 2.32 (d, J=13.4 Hz, 1H),
2.17-2.07 (m, 1H), 2.01-1.88 (m, 2H), 1.82 (d, J=13.4 Hz, 2H), 1.74
(s, 3H), 1.72-1.64 (m, 2H), 1.57-1.34 (m, 8H), 1.27-1.19 (m, 2H),
1.13 (dd, J=12.7, 3.7 Hz, 1H), 1.06 (s, 3H), 0.97 (s, 3H), 0.92 (s,
6H), 0.82 (s, 3H).
Step 2. To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(1-(2-(1,1-dioxidothiomorp-
holino)ethyl)-1H-1,2,4-triazol-3-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-e-
n-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1-
H-cyclopenta[a]chrysen-9-yl)benzoate, TFA (12.1 mg, 0.014 mmol) in
THF (1 mL) and MeOH (0.25 mL) was added a solution of 1N lithium
hydroxide (0.056 mL, 0.056 mmol). The reaction was stirred at
75.degree. C. After 1 h, the reaction was cooled to rt and purified
by reverse phase HPLC using HPLC method 5 to give
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(1-(2-(1,1-dioxidothiomorp-
holino)ethyl)-1H-1,2,4-triazol-3-yl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-e-
n-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1-
H-cyclopenta[a]chrysen-9-yl)benzoic acid, TFA (11.3 mg, 91% yield)
as a white solid. LC/MS: m/e 743.4 (M+H).sup.+, 4.80 min (method
3). .sup.1H NMR (400 MHz, CHLOROFORM-d) .delta. 9.24 (s, 1H), 7.99
(d, J=8.3 Hz, 2H), 7.23 (d, J=8.3 Hz, 2H), 5.31 (d, J=4.6 Hz, 1H),
4.76 (s, 1H), 4.66 (s, 1H), 4.40 (t, J=5.7 Hz, 2H), 3.17-3.10 (m,
2H), 3.09-3.04 (m, 8H), 3.03-2.99 (m, 1H), 2.54 (td, J=12.2, 3.3
Hz, 1H), 2.34 (d, J=13.7 Hz, 1H), 2.13 (dd, J=17.2, 6.2 Hz, 1H),
2.01-1.86 (m, 2H), 1.84-1.79 (m, 1H), 1.75 (s, 3H), 1.73-1.59 (m,
3H), 1.57-1.34 (m, 8H), 1.31-1.17 (m, 3H), 1.16-1.08 (m, 2H), 1.06
(s, 3H), 0.97 (s, 3H), 0.94 (s, 6H), 0.81 (s, 3H). .sup.13C NMR
(101 MHz, CHLOROFORM-d) .delta. 183.4, 170.4, 164.3, 161.7, 150.0,
149.5, 146.3, 143.0, 130.2, 129.1, 127.0, 124.0, 110.1, 77.2 (br.
s., 1C), 63.3, 55.3, 52.8, 51.1 (d, J=2.3 Hz, 1C), 50.6, 49.6,
49.4, 48.5, 46.7, 42.6, 41.7, 40.7, 39.2, 37.6, 37.5, 36.3, 33.5
(br. s., 1C), 30.1, 29.4, 28.6, 25.4, 21.4, 21.1, 19.7, 19.3, 16.5,
15.6, 14.8.
Example 7
Preparation of
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a--
(1-methyl-1H-1,2,4-triazol-5-yl)-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7-
a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)be-
nzoic acid
##STR00025## Step 1. Preparation of
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a--
(1-methyl-1H-1,2,4-triazol-5-yl)-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7-
a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)be-
nzoate.
To a solution mixture of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(E)-((dimethylamino)methyl-
ene)carbamoyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,-
5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-
-9-yl)benzoate (60 mg, 0.096 mmol) and methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(formylcarbamoyl)-5a,5b,8,-
8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,-
12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate
(57.4 mg, 0.096 mmol) in glacial acetic acid (2 mL) was added
methylhydrazine (0.036 mL, 0.670 mmol). The reaction was stirred at
90.degree. C. After 16 h, the reaction was cooled to rt and
concentrated to a brown viscous oil. Crude material was purified by
reverse phase prep-HPLC using HPLC method 2 and dried in vacuo to
give the title compound (12.7 mg, 21.76% yield) as a white solid.
LC/MS: m/e 610.3 (M+H).sup.+, 6.61 min (method 3). .sup.1H NMR (400
MHz, CHLOROFORM-d) .delta. 8.18 (s, 1H), 7.93 (d, J=8.6 Hz, 2H),
7.20 (d, J=8.6 Hz, 2H), 5.30 (dd, J=6.2, 1.8 Hz, 1H), 4.82 (d,
J=1.5 Hz, 1H), 4.70-4.65 (m, 1H), 4.02 (s, 3H), 3.91 (s, 3H), 3.16
(td, J=11.1, 4.5 Hz, 1H), 2.86 (td, J=12.3, 3.4 Hz, 1H), 2.39-2.31
(m, 1H), 2.14 (dd, J=17.1, 6.4 Hz, 1H), 2.06-1.99 (m, 1H),
1.98-1.90 (m, 1H), 1.84-1.77 (m, 1H), 1.75 (s, 3H), 1.72-1.64 (m,
3H), 1.63-1.53 (m, 2H), 1.52-1.38 (m, 7H), 1.38-1.30 (m, 1H),
1.24-1.16 (m, 2H), 1.05 (s, 3H), 1.02 (d, J=1.5 Hz, 1H), 0.97 (s,
3H), 0.92 (s, 6H), 0.83 (s, 3H).
Step 2: To a solution of methyl
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a--
(1-methyl-1H-1,2,4-triazol-5-yl)-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7-
a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)be-
nzoate (12.7 mg, 0.021 mmol) in THF (1 mL) and MeOH (0.25 mL) was
added a solution of 1N lithium hydroxide (0.073 mL, 0.073 mmol).
The reaction was stirred at 75.degree. C. After 1 h, the reaction
was cooled to rt and purified by reverse phase prep-HPLC using HPLC
method 4 and dried in vacuo to give
4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a--
(1-methyl-1H-1,2,4-triazol-5-yl)-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7-
a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)be-
nzoic acid (9.1 mg, 0.015 mmol, 70.4% yield) as a white solid.
LC/MS: m/e 596.3 (M+H).sup.+, 5.33 min (method 3). .sup.1H NMR (400
MHz, 1:1 CDCl.sub.3:METHANOL-d.sub.4) .delta. 7.89 (d, J=8.3 Hz,
2H), 7.78 (s, 1H), 7.17 (d, J=8.6 Hz, 2H), 5.30-5.22 (m, 1H), 4.77
(d, J=1.7 Hz, 1H), 3.93 (s, 3H), 3.23-3.05 (m, 2H), 2.33 (d, J=13.7
Hz, 1H), 2.11 (dd, J=17.2, 6.2 Hz, 1H), 2.04-1.96 (m, 1H),
1.93-1.80 (m, 2H), 1.72 (s, 3H), 1.68 (d, J=16.4 Hz, 1H), 1.63-1.58
(m, 1H), 1.55-1.30 (m, 10H), 1.28-1.19 (m, 2H), 1.18-1.08 (m, 2H),
1.04 (s, 3H), 0.97 (s, 3H), 0.90 (s, 6H), 0.82 (s, 3H). HIV cell
culture assay--MT-2 cells and 293T cells were obtained from the NIH
AIDS Research and Reference Reagent Program. MT-2 cells were
propagated in RPMI 1640 media supplemented with 10% heat
inactivated fetal bovine serum, 100 .mu.g/mL penicillin G and up to
100 units/mL streptomycin. The 293T cells were propagated in DMEM
media supplemented with 10% heat inactivated fetal bovine serum
(FBS), 100 units/mL penicillin G and 100 .mu.g/mL streptomycin. The
proviral DNA clone of NL.sub.4-3 was obtained from the NIH AIDS
Research and Reference Reagent Program. A recombinant NL.sub.4-3
virus, in which a section of the nef gene from NL4-3 was replaced
with the Renilla luciferase gene, was used as a reference virus. In
addition, residue Gag P373 was converted to P373S. Briefly, the
recombinant virus was prepared by transfection of the altered
proviral clone of NL.sub.4-3. Transfections were performed in 293T
cells using LipofectAMINE PLUS from Invitrogen (Carlsbad, Calif.),
according to manufacturer's instruction. The virus was titered in
MT-2 cells using luciferase enzyme activity as a marker. Luciferase
was quantitated using the Dual Luciferase kit from Promega
(Madison, Wis.), with modifications to the manufacturer's protocol.
The diluted Passive Lysis solution was pre-mixed with the
re-suspended Luciferase Assay Reagent and the re-suspended Stop
& Glo Substrate (2:1:1 ratio). Fifty (50) .mu.L of the mixture
was added to each aspirated well on assay plates and luciferase
activity was measured immediately on a Wallac TriLux
(Perkin-Elmer). Antiviral activities of inhibitors toward the
recombinant virus were quantified by measuring luciferase activity
in cells infected for 4-5 days with NLRluc recombinants in the
presence serial dilutions of the inhibitor. The EC.sub.50 data for
the compounds is shown in Table 1. Biological Data Key for
EC.sub.50
TABLE-US-00002 Compounds with EC.sub.50 > 0.1 .mu.M Compounds
with EC.sub.50 .ltoreq. 0.1 .mu.M Group "B" Group "A"
TABLE-US-00003 TABLE 1 Example WT EC50 # Structure .mu.M 1
##STR00026## 0.08 2 ##STR00027## B 3 ##STR00028## A 4 ##STR00029##
A 5 ##STR00030## A 6 ##STR00031## A 7 ##STR00032## A
The foregoing description is merely illustrative and should not be
understood to limit the scope or underlying principles of the
invention in any way. Indeed, various modifications of the
invention, in addition to those shown and described herein, will
become apparent to those skilled in the art from the following
examples and the foregoing description. Such modifications are also
intended to fall within the scope of the appended claims.
* * * * *
References